OMERO.server upgrade

The OME team is committed to providing frequent, project-wide upgrades both with bug fixes and new functionality. We try to make the schedule for these releases as public as possible. You may want to take a look at the Trello boards for exactly what will go into a release. See also OMERO.web upgrade.

See the full details of OMERO 5.6.10 features in the CHANGELOGS.

This guide aims to be as definitive as possible so please do not be put off by the level of detail; upgrading should be a straightforward process.


If you are upgrading from a version prior to OMERO 5.5 then you must also study the upgrade instructions for those prior versions because they may describe important steps that these instructions assume to already have been done by OMERO 5.5 users. Before proceeding with these instructions you may first need to read the instructions for upgrading to OMERO 5.5 because some extra steps may be required beyond simply running the SQL upgrade scripts described below.

Upgrade checklist

Check prerequisites

Before starting the upgrade, please ensure that you have reviewed and satisfied all the system requirements with correct versions for installation. In particular, ensure that you are running a suitable version of PostgreSQL to enable successful upgrading of the database, otherwise the upgrade script aborts with a message saying that your database server version is less than the OMERO prerequisite.

File limits

You may wish to review the open file limits. Please consult the Too many open file descriptors section for further details.

Password usage

The passwords and logins used here are examples. Please consult the Which user account and password do I use where? section for explanation. In particular, be sure to replace the values of db_user and omero_database with the actual database user and database name for your installation.

Memoization files invalidation

All cached Bio-Formats memoization files created at import time will be invalidated by the server upgrade. This means the very first loading of each image after upgrade will be slower. After re-initialization, a new memoization file will be automatically generated and OMERO will be able to load images in a performant manner again.

These files are stored under BioFormatsCache in the OMERO data directory, e.g. /OMERO/BioFormatsCache. You may see error messages in your log files when an old memoization file is found; to avoid these messages delete everything under this directory before starting the upgraded server.

It is possible to regenerate the memoization files before the user loads an image for the first time. For more information, read


If you encounter errors during an OMERO upgrade, database upgrade, etc., you should retain as much log information as possible and notify the OMERO.server team via the forum.

Upgrade check

All OMERO products check themselves with the OmeroRegistry for update notifications on startup. If you wish to disable this functionality you should do so now as outlined on the OMERO upgrade checks page.

Upgrade steps

For all users, the basic workflow for upgrading your OMERO.server is listed below. Please refer to each section for additional details.

Check ahead for upgrade issues

There is a precheck SQL script provided that performs various database checks to verify readiness for upgrade. The precheck script works even with the OMERO server running so it may be used before downtime for the actual upgrade is scheduled. Issues that the script reports will need to be resolved before the upgrade may proceed. The precheck script will not make any changes to the database: it merely performs various precautionary checks also done by the actual upgrade script.

$ cd OMERO.server
$ psql -h localhost -U db_user omero_database < sql/psql/OMERO5.4__0/OMERO5.3__1-precheck.sql
Password for user db_user:

(1 row)


The sql/psql/OMERO5.4__0/OMERO5.3__1-precheck.sql script referenced by the above psql command assumes a planned upgrade from OMERO 5.3.4. If you are instead currently running OMERO 5.3.3 or an earlier 5.3.x version then you perform the precheck by using the above command with sql/psql/OMERO5.4__0/OMERO5.3__0-precheck.sql. That script verifies that the database contains no trace of having been exploited; this vulnerability was fixed in OMERO 5.3.4.

Perform a database backup

The first thing to do before any upgrade activity is to backup your database.

$ pg_dump -h localhost -U db_user -Fc -f before_upgrade.db.dump omero_database

Copy new binaries

Before copying the new binaries, stop the existing server:

$ cd OMERO.server
$ omero admin stop

Your OMERO configuration is stored using config.xml in the etc/grid directory under your OMERO.server directory. Assuming you have not made any file changes within your OMERO.server distribution directory, you are safe to follow the following upgrade procedure:

$ cd ..
$ mv OMERO.server OMERO.server-old
$ unzip
$ ln -s OMERO.server-||version_openmicroscopy|-ice36 OMERO.server
$ cp OMERO.server-old/etc/grid/config.xml OMERO.server/etc/grid

Upgrade your database


This section only concerns users upgrading from a 5.3 or earlier server. If upgrading from a 5.4 or 5.5 server, you do not need to upgrade the database.

Ensure Unicode character encoding

OMERO requires a Unicode-encoded database; without it, the upgrade script aborts with a message warning how the OMERO database character encoding must be UTF8. From psql:

# SELECT datname, pg_encoding_to_char(encoding) FROM pg_database;
  datname   | pg_encoding_to_char
 template1  | UTF8
 template0  | UTF8
 postgres   | UTF8
 omero      | UTF8
(4 rows)

Alternatively, simply run psql -l and check the output. If your OMERO database is not Unicode-encoded with UTF8 then it must be re-encoded.

If you have the pg_upgradecluster command available then its --locale option can effect the change in encoding. Otherwise, create a Unicode-encoded dump of your database: dump it as before but to a different dump file and with an additional -E UTF8 option. Then, create a Unicode-encoded database for OMERO and restore that dump into it with pg_restore, similarly to effecting a rollback. If required to achieve this, the -E UTF8 option is accepted by both initdb and createdb.

Run the upgrade script

You must use the same username and password you have defined during OMERO.server installation. For a large production system you should plan for the fact that the upgrade script may take several hours to run.

$ cd OMERO.server
$ psql -h localhost -U db_user omero_database < sql/psql/OMERO5.4__0/OMERO5.3__1.sql
Password for user db_user:

(1 row)

If you are upgrading from a server earlier than 5.3, then you must run the earlier upgrade scripts in sequence before the one above. There is no need to download and run the server from an intermediate major release but you must still study the upgrade instructions for earlier versions in case there are additional steps. For example, any optional SQL scripts that affect the database probably run only on the specific version before the next upgrade script.


If you perform the database upgrade using SQL shell, make sure you are connected to the database using db_user before running the script. See this forum thread for more information.


The sql/psql/OMERO5.4__0/OMERO5.3__1.sql script referenced by the above psql command assumes upgrade from OMERO 5.3.4. If you are instead currently running OMERO 5.3.3 or an earlier 5.3.x version then you upgrade the database directly to OMERO 5.4.0 by using the above command with sql/psql/OMERO5.4__0/OMERO5.3__0.sql.

Optimize an upgraded database (optional)

After you have run the upgrade script, you may want to optimize your database which can both save disk space and speed up access times.

$ psql -h localhost -U db_user omero_database -c 'VACUUM FULL VERBOSE ANALYZE;'

Merge script changes

If any new official scripts have been added under lib/scripts or if you have modified any of the existing ones, then you will need to backup your modifications. Doing this, however, is not as simple as copying the directory over since the core developers will have also improved these scripts.

For further information on managing your scripts, refer to OMERO.scripts. If you require help, please contact the OME developers.

Update your environment variables and memory settings

Environment variables

If you changed the directory name where the 5.6.10 server code resides, make sure to update any system environment variables. Before restarting the server, make sure your PATH system environment variable is pointing to the new location. Also make sure the OMERODIR environment variable is set to the location of the server.

See Environment variables for more information.

JVM memory settings

Your memory settings should be copied along with etc/grid/config.xml, but you can check the current settings by running omero admin jvmcfg. See Memory configuration for more information.


While upgrading the server you should keep dependencies up to date to ensure that security updates are applied:

$ # first, activate virtualenv where omero-py is installed. Then upgrade:
$ pip install --upgrade 'omero-py>=5.17.0'

Server certificate

The server should be configured with at least a self-signed certificate to allow clients to establish secure connections.

Since OMERO 5.6.2, the recommended way to ensure that all OMERO server installations have at minimum, a self-signed certificate is to use the omero-certificates plugin. The plugin will generate or update your self-signed certificates and configure the OMERO.server. For the configuration to take effect, the server needs to be restarted. If you prefer to configure the OMERO server certificate manually, check Client Server SSL verification.

If your server has been configured with a version of omero-certificates older than 0.3.0 or manually, the configuration may need to be upgraded in particular to disallow the deprecated TLS 1.0 and 1.1 protocols.

To do so, activate the virtual environment where the server Python dependencies are installed, upgrade omero-certificates to version 0.3.0 or later, remove the omero.glacier2.IceSSL.Protocols and omero.glacier2.IceSSL.ProtocolVersionMax configurations and finally re-execute the omero certificates command:

$ pip install "omero-certificates>=0.3"
$ omero config set omero.glacier2.IceSSL.Protocols
$ omero config set omero.glacier2.IceSSL.ProtocolVersionMax
$ omero certificates


From version 0.3.0, the omero certificates command adds TLS 1.3 to the list of TLS protocols allowed assuming the OMERO.server enviroment supports the protocol. In order to negotiate this protocol, clients will also need to be upgraded to depend on omero-blitz 5.7.0 or greater (Java) or omero-py 5.15.0 or greater (Python).

Restart your server

  • Following a successful database upgrade, you can start the server.

    $ omero admin start
  • If anything goes wrong, please send the output of omero admin diagnostics to the forum.

Restore a database backup

If the upgraded database or the new server version do not work for you, or you otherwise need to rollback to a previous database backup, you may want to restore a database backup. To do so, create a new database,

$ createdb -h localhost -U postgres -E UTF8 -O db_user omero_from_backup

restore the previous archive into this new database,

$ pg_restore -Fc -d omero_from_backup before_upgrade.db.dump

and configure your server to use it.

$ omero config set omero_from_backup