Configuration properties glossary


The primary form of configuration is via the use of key/value properties, stored in etc/grid/config.xml and read on server startup. Backing up and copying these properties is as easy as copying this file to a new server version.

The file of your distribution defines all the default configuration properties used by the server. Changes made to the file are not recognized by the server. Instead, configuration options can be set using the omero config set command:

$ omero config set <parameter> <value>

When supplying a value with spaces or multiple elements, use single quotes. The quotes will not be saved as part of the value (see below).

To remove a configuration option (to return to default values where mentioned), simply omit the value:

$ omero config set <parameter>

These options will be stored in a file: etc/grid/config.xml which you can read for reference. DO NOT edit this file directly.

You can also review all your settings by using:

$ omero config get

which should return values without quotation marks.

A final useful option of omero config edit is:

$ omero config edit

which will allow for editing the configuration in a system-default text editor.


Please use the escape sequence \" for nesting double quotes (e.g. "[\"foo\", \"bar\"]") or wrap with ' (e.g. '["foo", "bar"]').

Examples of doing this are on the server installation page, as well as the LDAP installation page.

Mandatory properties

The following properties need to be correctly set for all installations of the OMERO.server. Depending on your set-up, default values may be sufficient.




  • omero.db.pass

Binary repository

property omero.checksum.supported


Checksum algorithms supported by the server for new file uploads, being any comma-separated non-empty subset of:

  • Adler-32

  • CRC-32

  • MD5-128

  • Murmur3-32

  • Murmur3-128

  • SHA1-160

  • File-Size-64

In negotiation with clients, this list is interpreted as being in descending order of preference.

Default: SHA1-160, MD5-128, Murmur3-128, Murmur3-32, CRC-32, Adler-32, File-Size-64


Default: /OMERO/

property omero.fs.repo.path


Value dynamically set during the build Template for FS managed repository paths. Allowable elements are:

%user%         bob
%userId%       4
%group%        bobLab
%groupId%      3
%year%         2011
%month%        01
%monthname%    January
%day%          01
%time%         15-13-54.014
%institution%  University of Dundee
%hash%         0D2D8DB7
%increment%    14
%subdirs%      023/613
%session%      c3fdd5d8-831a-40ff-80f2-0ba5baef448a
%sessionId%    592
%perms%        rw----
%thread%       Blitz-0-Ice.ThreadPool.Server-3
/              path separator
//             end of root-owned directories

These are described further at FS configuration options

The path must be unique per fileset to prevent upload conflicts, which is why %time% includes milliseconds.

A // may be used as a path separator: the directories preceding it are created with root ownership, the remainder are the user’s. At least one user-owned directory must be included in the path.

The template path is created below omero.managed.dir, e.g. /OMERO/ManagedRepository/$omero.fs.repo.path/

Default: %user%_%userId%//%year%-%month%/%day%/%time%

property omero.fs.repo.path_rules


Rules to apply to judge the acceptability of FS paths for writing into omero.managed.dir, being any comma-separated non-empty subset of:

  • Windows required

  • Windows optional

  • UNIX required

  • UNIX optional

  • local required

  • local optional

Minimally, the “required” appropriate for the server is recommended. Also applying “optional” rules may make sysadmin tasks easier, but may be more burdensome for users who name their files oddly. “local” means “Windows” or “UNIX” depending on the local platform, the latter being applied for Linux and Mac OS X.

Default: Windows required, UNIX required

property omero.managed.dir


Default: ${}/ManagedRepository


property omero.client.browser.thumb_default_size


The default thumbnail size

Default: 96

property omero.client.download_as.max_size


Clients disable download as jpg/png/tiff above max pixel count.

Default: 144000000

property omero.client.icetransports


Comma separated list of Ice transports available to clients. The default value (“ssl,tcp”) instructs Ice to open the ports specified by the omero.ports.ssl and omero.ports.tcp properties. Restricting to “ssl” will prevent all non-encrypted connections to the OMERO server.

Additionally, there are two experimental values for using websockets: “ws” and “wss” for unencrypted and encrypted, respectively. The ports that are opened are controlled by the and omero.ports.wss properties. To enable all possible protocols use: “ssl,tcp,wss,ws”.

Note: When using websockets behind a web server like nginx, additional configuration may be needed.

Default: ssl, tcp

property omero.client.scripts_to_ignore


Server-side scripts used in IScript service Clients shouldn’t display.

Default: /omero/figure_scripts/, /omero/figure_scripts/, /omero/figure_scripts/, /omero/figure_scripts/, /omero/export_scripts/, /omero/import_scripts/


Flag to show/hide colleagues

Default: true


Client dropdown menu colleagues label.

Default: Members


Flag to show/hide all users.

Default: true


Client dropdown menu all users label.

Default: All Members


Flag to show/hide leader.

Default: true


Client dropdown menu leader label.

Default: Owners

property omero.client.ui.tree.orphans.description


Description of the “Orphaned images” container.

Default: This is a virtual container with orphaned images. These images are not linked anywhere. Just drag them to the selected container.

property omero.client.ui.tree.orphans.enabled


Flag to show/hide “Orphaned images” container. Only accept “true” or “false”

Default: true


Name of the “Orphaned images” container located in client tree data manager.

Default: Orphaned Images

property omero.client.ui.tree.type_order


Client tree type order rank list first type is ranked 1 (the highest), last is the lowest if set to ‘false’ empty list allows mixing all types and sorting them by default client ordering strategy

Default: tagset, tag, project, dataset, screen, plate, acquisition, image

property omero.client.viewer.initial_zoom_level


Initial client image viewer zoom level for big images

Default: 0

property omero.client.viewer.interpolate_pixels


Client viewers interpolate pixels by default.

Default: true

property omero.client.viewer.roi_limit


Client viewers roi limit.

Default: 2000


Absolute omeroweb host http(s)://your_domain/prefix/

Default: [empty]


property omero.db.authority


The string that will be used as the base for LSIDs in all exported OME objects including OME-XML and OME-TIFF. It’s usually not necessary to modify this value since the database UUID (stored in the database) is sufficient to uniquely identify the source.


property omero.db.dialect


Implementation of the org.hibernate.dialect.Dialect interface which will be used to convert HQL queries and save operations into SQL SELECTs and DML statements.

(PostgreSQL default)

Default: ome.util.PostgresqlDialect

property omero.db.driver


JDBC driver used to access the database. Other drivers can be configured which wrap this driver to provide logging, monitoring, etc.

(PostgreSQL default)

Default: org.postgresql.Driver


The host name of the machine on which the database server is running. A TCP port must be accessible from the server on which OMERO is running.

Default: localhost


The name of the database instance to which OMERO will connect.

Default: omero

property omero.db.pass


The password to use to connect to the database server

Default: omero

property omero.db.patch


The patch version of the database which is in use. This value need not match the patch version of the server that is is being used with. Any changes by developers to the database schema will result in a bump to this value.

Default: 0

property omero.db.poolsize


Sets the number of database server connections which will be used by OMERO.

A sizeable increase in this value, e.g. to 100, will significantly increase the performance of your server, but your database installation will need to be configured to accept at least as many, preferably more, connections as this value.

The related values omero.threads.max_threads and omero.threads.background_threads do not need to be increased by the same amount. A system will be more stable if background_threads is less than max_threads and max_threads is less than poolsize.

Default: 10

property omero.db.port


TCP port on which the database server is listening for connections. Used by the JDBC driver to access the database. Use of a local UNIX socket is not supported.

(PostgreSQL default)

Default: 5432

property omero.db.prepared_statement_cache_size


Default: 10

property omero.db.profile


Default values for the current profile will be hard-coded into the file in the model-*.jar. By using a different jar, you can modify the defaults.

Note: some other properties are defined in the file etc/profiles/$omero.db.profile Especially of importance is omero.db.port Set during the build

Default: psql


Properties to set on OMERO.server’s JDBC connection to the database. See

Default: [empty]

property omero.db.sql_action_class


Implementation of the ome.util.SqlAction interface which will be used to perform all direct SQL actions, i.e. without Hibernate.

(PostgreSQL default)

Default: ome.util.actions.PostgresSqlAction

property omero.db.statistics


Whether JMX statistics are collected for DB usage (by Hibernate, etc)

Default: true

property omero.db.url


The URL specifying how the Java driver connects to the database system.

Default: jdbc:postgresql://${}:${omero.db.port}/${}?ApplicationName=OMERO.${}&${}

property omero.db.user


The username to use to connect to the database server

Default: omero

property omero.db.version


Version of the database which is in use. This value typically matches the major.minor version of the server that it is being used with. Typically, only developers will change this version to bump to a new major version.

Default: OMERO5.4


property omero.glacier2.IceSSL


Glacier2Template IceSSL defaults and overrides, see Any property beginning omero.glacier2.IceSSL. will be used to update the corresponding IceSSL. property.

Default: [empty]

property omero.glacier2.IceSSL.Ciphers


Glacier2Template SSL allowed cipher suites


property omero.glacier2.IceSSL.ProtocolVersionMax


Glacier2Template SSL maximum allowed protocol (mac bug)

Default: tls1_1

property omero.glacier2.IceSSL.Protocols


Glacier2Template SSL allowed protocols

Default: tls1

property omero.glacier2.IceSSL.VerifyPeer


Glacier2Template SSL verification requirements

Default: 0


property omero.cluster.read_only


Deprecated. If true, will override both the db and repo properties to be true.

Default: false

property omero.cluster.read_only.db


If access to the database is read-only: no writes should be attempted. A “false” may be overridden by omero.cluster.read_only above.

Default: false

property omero.cluster.read_only.repo


If access to the binary repo is read-only: no writes should be attempted. A “false” may be overridden by omero.cluster.read_only above.

Default: false

property omero.cluster.redirector


Default: nullRedirector

property omero.grid.registry_timeout


registry_timeout is the milliseconds which the registry and other services will wait on remote services to respond.

Default: 5000


property Ice.IPv6


Disable IPv6 by setting to 0. Only needed in certain situations.

Default: 1


property omero.jvmcfg.append


Contains other parameters which should be passed to the JVM. The value of “append” is treated as if it were on the command line so will be separated on whitespace. For example, ‘-XX:-PrintGC -XX:+UseCompressedOops’ would results in two new arguments. Note that when using config set from the command line one may need to give a prior option to prevent a value starting with - from already being parsed as an option, and values may need quoting to prevent whitespace or other significant characters from being interpreted prematurely.

Default: [empty]

property omero.jvmcfg.heap_dump


Toggles on or off heap dumps on OOMs. Default is “off”. The special value “tmp” will create the heap dumps in your temp directory.

Default: [empty]

property omero.jvmcfg.heap_size


Explicit value for the -Xmx argument, e.g. “1g”

Default: [empty]

property omero.jvmcfg.max_system_memory


Suggestion for strategies as to the maximum memory that they will use for calculating JVM settings (MB).

Default: 48000

property omero.jvmcfg.min_system_memory


Suggestion for strategies as to the minimum memory that they will use for calculating JVM settings (MB).

Default: 3414

property omero.jvmcfg.percent


Used only by the percent strategy. An integer between 0 and 100 which is the percent of active memory that will be used by the service.

Default: [empty]

property omero.jvmcfg.perm_gen


Explicit value for the MaxPermSize argument to the JVM, e.g. “500M”. Ignored for Java8+

Default: [empty]

property omero.jvmcfg.strategy


Memory strategy which will be used by default. Options include: percent, manual

Default: percent

property omero.jvmcfg.system_memory


Manual override of the total system memory that OMERO will think is present on the local OS (MB). If unset, an attempt will be made to detect the actual amount: first by using the Python library psutil and if that is not installed, by running a Java tool. If neither works, 4.0GB is assumed.

Default: [empty]


property omero.ldap.base


LDAP server base search DN, i.e. the filter that is applied to all users. (can be empty in which case any LDAP user is valid)

Default: ou=example, o=com

property omero.ldap.config


Enable or disable LDAP (true or false).

Default: false

property omero.ldap.connect_timeout


Sets com.sun.jndi.ldap.connect.timeout on the Spring LDAP default security context source environment. The context source is responsible for interacting with JNDI/LDAP.

This timeout is specified in milliseconds and controls the amount of time JNDI/LDAP will wait for a connection to be established.

A timeout less than or equal to zero means that no timeout will be observed and that the OMERO server will wait indefinitely for LDAP connections to be established. Such a timeout should be used with extreme caution as connectivity issues may then cause your server to no longer be able to create new sessions.

For more information on what this JNDI/LDAP property does, see

Default: 5000

property omero.ldap.group_filter


Default: (objectClass=groupOfNames)

property omero.ldap.group_mapping


Default: name=cn

property omero.ldap.new_user_group


Without a prefix the “new_user_group” property specifies the name of a single group which all new users will be added to. Other new_user_group strings are prefixed with :x: and specify various lookups which should take place to find one or more target groups for the new user.

:ou: uses the final organizational unit of a user’s dn as the single OMERO group e.g. omero.ldap.new_user_group=:ou:

:attribute: uses all the values of the specified attribute as the name of multiple OMERO groups. e.g. omero.ldap.new_user_group=:attribute:memberOf

Like :attribute:, :filtered_attribute: uses all the values of the specified attribute as the name of multiple OMERO groups but the attribute must pass the same filter as :query: does. e.g. omero.ldap.new_user_group=:filtered_attribute:memberOf

Similar to :attribute:, :dn_attribute: uses all the values of the specified attribute as the DN of multiple OMERO groups. e.g. omero.ldap.new_user_group=:dn_attribute:memberOf

A combination of filtered_attribute and dn_attribute, :filtered_dn_attribute: uses all of the values of the specified attribute as the DN of multiple OMERO groups but the attribute must pass the same filter as :query: e.g. omero.ldap.new_user_group=:filtered_dn_attribute:memberOf

:query: performs a query for groups. The “name” property will be taken as defined by omero.ldap.group_mapping and the resulting filter will be AND’ed with the value group_filter (above) e.g. omero.ldap.new_user_group=:query:(member=@{dn})

:bean: looks in the server’s context for a bean with the given name which implements e.g. omero.ldap.new_user_group=:bean:myNewUserGroupMapperBean

Default: default

property omero.ldap.new_user_group_owner


A query element to check if user who is being created via the new_user_group setting should be made a “manager”, i.e. owner, of the queried group. E.g. omero.ldap.new_user_group_owner=(owner=@{dn}) will use the ‘manager’ attribute to set the ‘owner’ flag in the database. This query element is appended to any query used by new_user_group with an AND.

This property is not used by new_user_group type ‘default’ and only potentially by :bean:.

Default: [empty]

property omero.ldap.password


LDAP server bind password (if required; can be empty)

Default: [empty]

property omero.ldap.read_timeout


Sets on the Spring LDAP default security context source environment. The context source is responsible for interacting with JNDI/LDAP.

This timeout is specified in milliseconds and controls the amount of time JNDI/LDAP will wait for a response from the LDAP server. When connecting to a server using SSL this timeout also applies to the SSL handshake process.

A timeout less than or equal to zero means that no timeout will be observed and that the OMERO server will wait indefinitely for LDAP replies. Such a timeout should be used with extreme caution, especially when using SSL and/or without a connection pool, as connectivity issues may then cause your server to no longer be able to create new sessions.

For more information on what this JNDI/LDAP property does, see

Default: 5000

property omero.ldap.referral


Available referral options are: “ignore”, “follow”, or “throw” as per the JNDI referral documentation.

Default: ignore

property omero.ldap.sync_on_login


Whether or not values from LDAP will be synchronized to OMERO on each login. This includes not just the username, email, etc, but also the groups that the user is a member of.


Admin actions carried out in the clients may not survive this synchronization e.g. LDAP users removed from an LDAP group in the UI will be re-added to the group when logging in again after the synchronization.

Default: false

property omero.ldap.urls


Set the URL of the LDAP server. A SSL URL for this property would be of the form: ldaps://

Default: ldap://localhost:389

property omero.ldap.user_filter


Default: (objectClass=person)

property omero.ldap.user_mapping


Default: omeName=cn, firstName=givenName, lastName=sn, email=mail, institution=department, middleName=middleName

property omero.ldap.username


LDAP server bind DN (if required; can be empty)

Default: [empty]


property omero.mail.bean


Mail sender properties

Default: defaultMailSender

property omero.mail.config


Enable or disable mail sender (true or false).

Default: false

property omero.mail.from


the email address used for the “from” field

Default: omero@${}


the hostname of smtp server

Default: localhost

property omero.mail.password


the password to connect to the smtp server (if required; can be empty)

Default: [empty]

property omero.mail.port


the port of smtp server

Default: 25

property omero.mail.smtp.auth


see javax.mail.Session properties

Default: false

property omero.mail.smtp.connectiontimeout


Default: 60000

property omero.mail.smtp.debug


Default: false

property omero.mail.smtp.socketFactory.class



property omero.mail.smtp.socketFactory.fallback


Default: false

property omero.mail.smtp.socketFactory.port


Default: ${omero.mail.port}

property omero.mail.smtp.starttls.enable


Default: false

property omero.mail.smtp.timeout


Default: 60000

property omero.mail.transport.protocol


other smtp parameters; see org.springframework.mail.javamail.JavaMailSenderImpl

Default: smtp

property omero.mail.username


the username to connect to the smtp server (if required; can be empty)

Default: [empty]


property omero.metrics.bean


Which bean to use: nullMetrics does nothing defaultMetrics uses the properties defined below

Default: defaultMetrics

property omero.metrics.graphite


Address for Metrics to send server data

Default: [empty]

property omero.metrics.slf4j_minutes


Number of minutes to periodically print to slf4j 0 or lower disables the printout.

Default: 60



Name of the OMERO component that is running in this process.

Default: Server


property omero.sessions.max_user_time_to_idle


Sets the maximum duration in milliseconds a user can request before a login is required due to inactivity.

Default: 6000000

property omero.sessions.max_user_time_to_live


Sets the maximum duration in milliseconds a user can request before a login is required (0 signifies never).

Default: 0

property omero.sessions.maximum


Sets the default duration before a login is required; 0 signifies never.

Default: 0

property omero.sessions.sync_force


Default: 1800000

property omero.sessions.sync_interval


Default: 120000

property omero.sessions.timeout


Sets the default duration of inactivity in milliseconds after which a login is required.

Default: 600000

property omero.threads.background_threads


Number of threads from the min_threads pool that can be used at any given time for background tasks like import. Note that if this value is less than min_threads, min_threads will limit the number of background tasks which can run simultaneously.

Default: 5

property omero.threads.background_timeout


Number of milliseconds to wait for a slot in the background queue before a rejection error will be raised.

Default: 3600000

property omero.threads.cancel_timeout


Default: 5000

property omero.threads.idle_timeout


This setting does nothing. See And

Default: 5000

property omero.threads.max_threads


This setting does nothing. See And

Default: 50

property omero.threads.min_threads


Maximum and minimum number of threads that can simultaneously run at the “USER” and “BACKGROUND” priority level. Internal system threads may still run. Note when setting this that these threads do not time out.

Default: 10

property omero.throttling.method_time.error


Time in milliseconds after which a single method invocation will print a ERROR statement to the server log. If ERRORs are frequently being printed to your logs, you may want to increase this value after checking that no actual problem exists. Values of more than 60000 (1 minute) are not advised.

Default: 20000

property omero.throttling.method_time.error.indexer


Value for the indexer is extended to 1 day

Default: 86400000

property omero.throttling.method_time.warn


Time in milliseconds after which a single method invocation will print a WARN statement to the server log.

Default: 5000

property omero.throttling.method_time.warn.indexer


Value for the indexer is extended to 1 hour

Default: 3600000

property omero.throttling.objects_read_interval


Default: 1000

property omero.throttling.objects_written_interval


Default: 1000

property omero.throttling.servants_per_session


Default: 10000


property omero.pixeldata.backoff


Name of the spring bean which will be used to calculate the backoff (in ms) that users should wait for an image to be ready to view.


property omero.pixeldata.backoff.default


A default value for the backoff time.

Default: 1000

property omero.pixeldata.backoff.maxpixels


The maximum number of pixels (in any dimension), if exceeded the default value will be used.

Default: 1000000

property omero.pixeldata.batch


Number of instances indexed per indexing. (Ignored by pixelDataEventLogQueue)

Default: 50

property omero.pixeldata.cron


Polling frequency of the pixeldata processing. Set empty to disable pixeldata processing.

Cron Format: seconds minutes hours day-of-month month day-of-week year (optional). For example, “0,30 * * * * ?” is equivalent to running every 30 seconds. See

Default: */4 * * * * ?

property omero.pixeldata.dispose


Whether the PixelData.dispose() method should try to clean up ByteBuffer instances which may lead to memory exceptions. See ticket #11675 for more information. Note: the property is set globally for the JVM.

Default: true

property omero.pixeldata.event_log_loader


EventLogLoader that will be used for loading EventLogs for the action “PIXELDATA”. Choices include: pixelDataEventLogQueue and the older pixelDataPersistentEventLogLoader

Default: pixelDataEventLogQueue

property omero.pixeldata.max_plane_float_override


If true, server will not require pyramids for floating point pixel types. Note that pyramids are never generated for floating point pixel types.

Default: true

property omero.pixeldata.max_plane_height


With omero.pixeldata.max_plane_width, specifies the plane size cutoff above which a pixel pyramid will be generated by the pixeldata service unless subresolutions can be read from the file format. These values will be ignored for floating or double pixel data types unlesss :property: omero.pixeldata.max_plane_float_override is set to false. Note pyramids are never generated for floating point pixel types.

Default: 3192

property omero.pixeldata.max_plane_width


With omero.pixeldata.max_plane_height, specifies the plane size cutoff above which a pixel pyramid will be generated by the pixeldata service unless subresolutions can be read from the file format. These values will be ignored for floating or double pixel data types unlesss :property: omero.pixeldata.max_plane_float_override is set to false. Note pyramids are never generated for floating point pixel types.

Default: 3192

property omero.pixeldata.max_projection_bytes


Specifies the maximum number of bytes the server will allow to be projected in real time with the rendering engine.

Default: 268435456

property omero.pixeldata.memoizer.dir


The directory in which Bio-Formats may create memo files for images from the managed repository.

Default: ${}/BioFormatsCache

property omero.pixeldata.memoizer.dir.local


For read-only servers set this to a local read-write directory so that memo files can be created and used. Activates only if the binary repository is read-only.

Default: [empty]

property omero.pixeldata.memoizer_wait


Maximum time in milliseconds that file parsing can take without the parsed metadata being cached to omero.pixeldata.memoizer.dir.

Default: 0

property omero.pixeldata.repetitions


Instead, it is possible to tell the server to run more pixeldata repetitions, each of which gets completely committed before the next. This will only occur when there is a substantial backlog of pixels to process.

(Ignored by pixelDataEventLogQueue; uses threads instead)

Default: 1

property omero.pixeldata.threads


How many pixel pyramids will be generated at a single time. The value should typically not be set to higher than the number of cores on the server machine.

Default: 2

property omero.pixeldata.tile_height


Default: 256

property omero.pixeldata.tile_sizes_bean


Default sizes for tiles are provided by a implementation. By default the bean (“configuredTileSizes”) uses the properties provided here.

Default: configuredTileSizes

property omero.pixeldata.tile_width


Default: 256


property omero.policy.bean


Instance of the PolicyService interface which will be responsible for checking certain server actions made by a user.

Default: defaultPolicyService

property omero.policy.binary_access


Configuration for the policy of whether users can access binary files from disk. Binary access includes all attempts to download a file from the UI.

The individual components of the string include:

  • write - whether or not users who have WRITE access to the objects can access the binary. This includes group and system administrators.

  • read - whether or not users who have READ access to the objects can access the binary.

  • image - whether or not images are to be considered accessible as a rule.

  • plate - whether or not plates and contained HCS objects are to be considered accessible as a rule. This includes wells, well samples, and plate runs.

Though the order of the components of the property are not important, the order that they are listed above roughly corresponds to their priority. E.g. a -write value will override +plate.

Example 1: “-read,+write,+image,-plate” only owners of an image and admins can download it.

Example 2: “-read,-write,-image,-plate” no downloading is possible.

Configuration properties of the same name can be applied to individual groups as well. E.g. adding, omero.policy.binary_access=-read to a group’s config property, you can prevent group-members from downloading original files, as at

Configuration is pessimistic: if there is a negative either on the group or at the server-level, the restriction will be applied. A missing value at the server restricts the setting but allows the server to override.

Default: +read, +write, +image


property omero.ports.prefix


The prefix to apply to all port numbers (SSL, TCP, registry) used by the server

Default: [empty]

property omero.ports.registry


The IceGrid registry port number to use

Default: 4061

property omero.ports.ssl


The Glacier2 SSL port number to use

Default: 4064

property omero.ports.tcp


The Glacier2 TCP port number to use (unencrypted)

Default: 4063


The Glacier2 WS port number to use (unencrypted)

Default: 4065

property omero.ports.wss


The Glacier2 WSS port number to use

Default: 4066



Base URL to use when sending feedback (errors, comments)



property omero.query.timeout


For the query service how many seconds before a query times out.

Default: 1000

property omero.query.timeout.admin


How many seconds before a query times out for administrative users.

Default: ${omero.query.timeout}


property omero.launcher.jython


Executable on the PATH which will be used for scripts with the mimetype ‘text/x-jython’.

Default: jython

property omero.launcher.matlab


Executable on the PATH which will be used for scripts with the mimetype ‘text/x-matlab’.

Default: matlab

property omero.launcher.python


Executable on the PATH which will be used for scripts with the mimetype ‘text/x-python’.

No value implies use sys.executable

Default: [empty]

property omero.process.jython


Server implementation which will be used for scripts with the mimetype ‘text/x-jython’. Changing this value requires that the appropriate class has been installed on the server.

Default: omero.processor.ProcessI

property omero.process.matlab


Server implementation which will be used for scripts with the mimetype ‘text/x-matlab’. Changing this value requires that the appropriate class has been installed on the server.

Default: omero.processor.MATLABProcessI

property omero.process.python


Server implementation which will be used for scripts with the mimetype ‘text/x-python’. Changing this value requires that the appropriate class has been installed on the server.

Default: omero.processor.ProcessI

property omero.scripts.cache.cron


Frequency to reload script params. By default, once a day at midnight.

Cron Format: seconds minutes hours day-of-month month day-of-week year (optional). For example, “0,30 * * * * ?” is equivalent to running every 30 seconds. See

Default: 0 0 0 * * ?

property omero.scripts.cache.spec


Guava LoadingCache spec for configuring how many script JobParams will be kept in memory for how long.

For more information, see

Default: maximumSize=1000

property omero.scripts.timeout


Default: 3600000



Default: groupChmodStrategy


Default: (int8and(permissions, %s) = %s)


Whether to ignore the case of the username during login (true or false). Default: false (JSmith and jsmith will be considered two different users).


Before enabling this feature, lower the case of all usernames in OMERO (omename column in the experimenter table). It is the system administrator’s responsibility to handle any username clashes.

Default: false


A keystore is a database of private keys and their associated X.509 certificate chains authenticating the corresponding public keys. A keystore is mostly needed if you are doing client-side certificates for authentication against your LDAP server.

Default: [empty]


Sets the password of the keystore

Default: [empty]


Default: 1


Default: 3000


Implementation of PasswordProvider that will be used to authenticate users. Typically, a chained password provider will be used so that if one form of authentication (e.g. LDAP) does not work, other attempts will be made.

Default: chainedPasswordProvider


Controls whether the server will allow creation of user accounts with an empty password. If set to true (default, strict mode), empty passwords are disallowed. This still allows the guest user to interact with the server.

Default: true


A truststore is a database of trusted entities and their associated X.509 certificate chains authenticating the corresponding public keys. The truststore contains the Certificate Authority (CA) certificates and the certificate(s) of the other party to which this entity intends to send encrypted (confidential) data. This file must contain the public key certificates of the CA and the client’s public key certificate.

Default: [empty]


Sets the password of the truststore

Default: [empty]


property omero.server.nodedescriptors


Override the default set of OMERO services. For example, to run OMERO.server with Blitz and Tables only (i.e. disable Processor, DropBox, Indexer, PixelData) set this to master:Blitz-0,Tables-0. Also use this to distribute OMERO services across multiple nodes, for example: master:Blitz-0,Tables-0 worker1:Processor-0. See

Default: [empty]


property omero.web.admins


A list of people who get code error notifications whenever the application identifies a broken link or raises an unhandled exception that results in an internal server error. This gives the administrators immediate notification of any errors, see OMERO.mail. Example:'[["Full Name", "email address"]]'.

Default: []

property omero.web.application_server


OMERO.web is configured to run in Gunicorn as a generic WSGI (TCP)application by default. Available options: wsgi-tcp (Gunicorn, default), wsgi (Advanced users only, e.g. manual Apache configuration with mod_wsgi).

Default: wsgi-tcp


The front-end webserver e.g. NGINX can be set up to run on a different host from OMERO.web. The property ensures that OMERO.web is accessible on an external IP. It requires copying all the OMERO.web static files to the separate NGINX server.


property omero.web.application_server.max_requests


The maximum number of requests a worker will process before restarting.

Default: 0

property omero.web.application_server.port


Upstream application port

Default: 4080

property omero.web.apps


Add additional Django applications. For example, see Creating an app

Default: []

property omero.web.base_include_template


Template to be included in every page, at the end of the <body>

Default: None

property omero.web.caches


OMERO.web offers alternative session backends to automatically delete stale data using the cache session store backend, see Django cached session documentation for more details.

Default: {\”default\”: {\”BACKEND\”: \”django.core.cache.backends.dummy.DummyCache\”}}

property omero.web.chunk_size


Size, in bytes, of the “chunk”

Default: 1048576

property omero.web.cors_origin_allow_all


If True, cors_origin_whitelist will not be used and all origins will be authorized to make cross-site HTTP requests.

Default: false

property omero.web.cors_origin_whitelist


A list of origin hostnames that are authorized to make cross-site HTTP requests. Used by the django-cors-headers app as described at

Default: []


A list of hosts which are trusted origins for unsafe requests. When starting with ‘.’, all subdomains are included. Example '["", ""]'. For more details see CSRF trusted origins.

Default: []

property omero.web.databases


Default: {}

property omero.web.debug


A boolean that turns on/off debug mode. Use debug mode only in development, not in production, as it logs sensitive and confidential information in plaintext.

Default: false

property omero.web.django_additional_settings


Additional Django settings as list of key-value tuples. Use this to set or override Django settings that aren’t managed by OMERO.web. E.g. ["CUSTOM_KEY", "CUSTOM_VALUE"]

Default: []

property omero.web.favicon_url


Favicon URL, specifies the path relative to django’s static file dirs.

Default: webgateway/img/ome.ico


Enable the feedback form for comments. These comments are sent to the URL in (OME team by default).

Default: true


Enable the feedback form for errors. These errors are sent to the URL in (OME team by default).

Default: true

property omero.web.html_meta_referrer


Default content for the HTML Meta referrer tag. See for allowed values and for browser compatibility. Warning: Internet Explorer 11 does not support the default value of this setting, you may want to change this to “origin” after reviewing the linked documentation.

Default: origin-when-crossorigin

property omero.web.index_template


Define template used as an index page http://your_host/omero/.If None user is automatically redirected to the login page.For example use ‘webclient/index.html’.

Default: None

property omero.web.logdir


A path to the custom log directory.

Default: /home/omero/OMERO.server/var/log

property omero.web.login.client_downloads_base


GitHub repository containing the Desktop client downloads

Default: ome/omero-insight

property omero.web.login.show_client_downloads


Whether to link to official client downloads on the login page

Default: true

property omero.web.login_incorrect_credentials_text


The error message shown to users who enter an incorrect username or password.

Default: Connection not available, please check your user name and password.


Redirect to the given location after logging in. It only supports arguments for Django reverse function. For example: '{"redirect": ["webindex"], "viewname": "load_template", "args":["userdata"], "query_string": {"experimenter": -1}}'

Default: {}

property omero.web.login_view


The Django view name used for login. Use this to provide an alternative login workflow.

Default: weblogin

property omero.web.max_table_download_rows


Prevent download of OMERO.tables exceeding this number of rows in a single request.

Default: 10000

property omero.web.maximum_multifile_download_size


Prevent multiple files with total aggregate size greater than this value in bytes from being downloaded as a zip archive.

Default: 1073741824

property omero.web.middleware


Warning: Only system administrators should use this feature. List of Django middleware classes in the form [{“class”: “”, “index”: FLOAT}]. See Django middleware. Classes will be ordered by increasing index

Default: [{\”index\”: 1, \”class\”: \”django.middleware.common.BrokenLinkEmailsMiddleware\”},{\”index\”: 2, \”class\”: \”django.middleware.common.CommonMiddleware\”},{\”index\”: 3, \”class\”: \”django.contrib.sessions.middleware.SessionMiddleware\”},{\”index\”: 4, \”class\”: \”django.middleware.csrf.CsrfViewMiddleware\”},{\”index\”: 5, \”class\”: \”django.contrib.messages.middleware.MessageMiddleware\”},{\”index\”: 6, \”class\”: \”django.middleware.clickjacking.XFrameOptionsMiddleware\”}]

property omero.web.nginx_server_extra_config


Extra configuration lines to add to the Nginx server block. Lines will be joined with n. Remember to terminate lines with; when necessary.

Default: []

property omero.web.open_with


A list of viewers that can be used to display selected Images or other objects. Each viewer is defined as ["Name", "url", options]. Url is reverse(url). Selected objects are added to the url as ?image=:1&image=2Objects supported must be specified in options with e.g. {"supported_objects":["images"]} to enable viewer for one or more images.

Default: [[\”Image viewer\”, \”webgateway\”, {\”supported_objects\”: [\”image\”],\”script_url\”: \”webclient/javascript/ome.openwith_viewer.js\”}]]

property omero.web.page_size


Number of images displayed within a dataset or ‘orphaned’ container to prevent from loading them all at once.

Default: 200

property omero.web.ping_interval


Timeout interval between ping invocations in seconds

Default: 60000

property omero.web.pipeline_css_compressor


Compressor class to be applied to CSS files. If empty or None, CSS files won’t be compressed.

Default: None

property omero.web.pipeline_js_compressor


Compressor class to be applied to JavaScript files. If empty or None, JavaScript files won’t be compressed.

Default: None

property omero.web.pipeline_staticfile_storage


The file storage engine to use when collecting static files with the collectstatic management command. See the documentation for more details.


property omero.web.plate_layout


If ‘shrink’, the plate will not display rows and columns before the first Well, or after the last Well. If ‘trim’, the plate will only show Wells from A1 to the last Well. If ‘expand’ (default), the plate will expand from A1 to a multiple of 12 columns x 8 rows after the last Well.

Default: expand

property omero.web.prefix


Used as the value of the SCRIPT_NAME environment variable in any HTTP request.

Default: None

property omero.web.public.cache.enabled


Default: false

property omero.web.public.cache.key


Default: omero.web.public.cache.key

property omero.web.public.cache.timeout


Default: 86400

property omero.web.public.enabled


Enable and disable the OMERO.web public user functionality.

Default: false

property omero.web.public.get_only


Restrict public users to GET requests only

Default: true

property omero.web.public.password


Password to use during authentication.

Default: None

property omero.web.public.server_id


Server to authenticate against.

Default: 1

property omero.web.public.url_filter


Set a regular expression that matches URLs the public user is allowed to access. If this is not set, no URLs will be publicly available.

Default: (?#This regular expression matches nothing)a^

property omero.web.public.user


Username to use during authentication.

Default: None

property omero.web.redirect_allowed_hosts


If you wish to allow redirects to an external site, the domains must be listed here. For example [“”].

Default: []

property omero.web.root_application


Override the root application label that handles /. Warning you must ensure the application’s URLs do not conflict with other applications. omero-gallery is an example of an application that can be used for this (set to gallery)

Default: [empty]


ID of the group to pre-select in search form. A value of 0 or -1 pre-selects All groups.

Default: 0


ID of the user to pre-select in search form. A value of 0 pre-selects the logged-in user. A value of -1 pre-selects All Users if the search is across all groups or All Members if the search is within a specific group.

Default: 0

property omero.web.secret_key


A boolean that sets SECRET_KEY for a particular Django installation.

Default: None


Force all backend OMERO.server connections to use SSL.

Default: false

property omero.web.secure_proxy_ssl_header


A tuple representing a HTTP header/value combination that signifies a request is secure. Example '["HTTP_X_FORWARDED_PROTO_OMERO_WEB", "https"]'. For more details see secure proxy ssl header.

Default: []

property omero.web.server_list


A list of servers the Web client can connect to.

Default: [[\”localhost\”, 4064, \”omero\”]]


Controls where Django stores session data. See Configuring the session engine for more details.Allowed values are: omeroweb.filesessionstore (deprecated), django.contrib.sessions.backends.db, django.contrib.sessions.backends.file, django.contrib.sessions.backends.cache or django.contrib.sessions.backends.cached_db.

Default: django.contrib.sessions.backends.file

property omero.web.session_expire_at_browser_close


A boolean that determines whether to expire the session when the user closes their browser. See Django Browser-length sessions vs. persistent sessions documentation for more details.

Default: true

property omero.web.session_serializer


You can use this setting to customize the session serialization format. See Django session serialization documentation for more details.

Default: django.contrib.sessions.serializers.PickleSerializer

property omero.web.sharing.opengraph


Dictionary of server-name: site-name, where server-name matches a name from omero.web.server_list. For example: '{"omero": "Open Microscopy"}'

Default: {}

property omero.web.sharing.twitter


Dictionary of server-name: @twitter-site-username, where server-name matches a name from omero.web.server_list. For example: '{"omero": "@openmicroscopy"}'

Default: {}

property omero.web.show_forgot_password


Allows to hide ‘Forgot password’ from the login view - useful for LDAP/ActiveDir installations

Default: true

property omero.web.static_root


The absolute path to the directory where collectstatic will collect static files for deployment. If the staticfiles contrib app is enabled (default) the collectstatic management command will collect static files into this directory.

Default: /home/omero/OMERO.server/var/static

property omero.web.static_url


URL to use when referring to static files. Example: '/static/' or ''. Used as the base path for asset definitions (the Media class) and the staticfiles app. It must end in a slash if set to a non-empty value.

Default: /static/

property omero.web.staticfile_dirs


Defines the additional locations the staticfiles app will traverse if the FileSystemFinder finder is enabled, e.g. if you use the collectstatic or findstatic management command or use the static file serving view.

Default: []

property omero.web.template_dirs


List of locations of the template source files, in search order. Note that these paths should use Unix-style forward slashes.

Default: []

property omero.web.thumbnails_batch


Number of thumbnails retrieved to prevent from loading them all at once. Make sure the size is not too big, otherwise you may exceed limit request line, see

Default: 50

property omero.web.time_zone


Time zone for this installation. Choices can be found in the TZ database name column of: Default "Europe/London"

Default: Europe/London


Add plugins to the center panels. Plugins are ['Channel overlay', 'webtest/webclient_plugins/center_plugin.overlay.js.html', 'channel_overlay_panel']. The javascript loads data into $('#div_id').

Default: []

property omero.web.ui.metadata_panes


Manage Metadata pane accordion. This functionality is limited to the existing sections.

Default: [{\”name\”: \”tag\”, \”label\”: \”Tags\”, \”index\”: 1},{\”name\”: \”map\”, \”label\”: \”Key-Value Pairs\”, \”index\”: 2},{\”name\”: \”table\”, \”label\”: \”Tables\”, \”index\”: 3},{\”name\”: \”file\”, \”label\”: \”Attachments\”, \”index\”: 4},{\”name\”: \”comment\”, \”label\”: \”Comments\”, \”index\”: 5},{\”name\”: \”rating\”, \”label\”: \”Ratings\”, \”index\”: 6},{\”name\”: \”other\”, \”label\”: \”Others\”, \”index\”: 7}]

property omero.web.ui.right_plugins


Add plugins to the right-hand panel. Plugins are ['Label', 'include.js', 'div_id']. The javascript loads data into $('#div_id').

Default: [[\”Acquisition\”, \”webclient/data/includes/right_plugin.acquisition.js.html\”, \”metadata_tab\”],[\”Preview\”, \”webclient/data/includes/right_plugin.preview.js.html\”, \”preview_tab\”]]


Specifies whether to use the X-Forwarded-Host header in preference to the Host header. This should only be enabled if a proxy which sets this header is in use.

Default: false

property omero.web.user_dropdown


Whether or not to include a user dropdown in the base template. Particularly useful when used in combination with the OMERO.web public user where logging in may not make sense.

Default: true

property omero.web.viewer.view


Django view which handles display of, or redirection to, the desired full image viewer.

Default: omeroweb.webclient.views.image_viewer

property omero.web.webgateway_cache


Default: None

property omero.web.wsgi_args


A string representing Gunicorn additional arguments. Check Gunicorn Documentation

Default: None

property omero.web.wsgi_timeout


Workers silent for more than this many seconds are killed and restarted. Check Gunicorn Documentation

Default: 60

property omero.web.wsgi_workers


The number of worker processes for handling requests. Check Gunicorn Documentation

Default: 5

property omero.web.x_frame_options


Whether to allow OMERO.web to be loaded in a frame.