Omero import error "Ice.SecurityException: javax.net.ssl.SSLHandshakeException: No appropriate protocol " again

Hi together,
I recently faced a problem that was discussed already before.
e.g. https://forum.image.sc/t/unable-to-use-cli-importer/26424

I tried the suggested fix with “–skip upgrade” but still get the same error.

My details:
OpenSSL version 1.1.1d
java version: openjdk 11.0.11
omero.py version 5.8.3
Omero.server version 5.6.1-ice36-b225

Since the problem just appeared I guess it is due to the recent update of openjdk (update 2021-04-20).

Any suggestions are appreciated.

Thanks
Alex

Hi @alexra

We are preparing a release to that effect and updating our doc.
I assume you are on CentOS 7.
You will need to install openssl and configure omero-certificates (this is already installed when $VENV_SERVER/bin/pip install omero-server[default] is run) to
i.e.
yum -y install openssl
and run omero certificates to configure the certificates.
For the steps described above, you need to follow the instructions from OMERO.server installation on CentOS 8 — OMERO 5.6.3 documentation

Cheers

Jmarie

Dear Jean-Marie,
thanks for the response. That sounds fine. I am on Debian, not on CentOS 7. Do I need to upgrade to Omero 5.6.3 before, or is this also valid for 5.6.1?
Thanks
Alex

@alexra for complete reference, relevant issues are Latest OpenJDK releases remove TLS 1.0/1.1 support · Issue #57 · ome/ansible-role-omero-server · GitHub and OMERO.server 5.6 upgrade · Issue #327 · IDR/deployment · GitHub. The import error is related to the fact that recent Java releases incl. OpenJDK 11.0.11 dropped support for TLS 1.0/1.1.

You might not necessarily need to upgrade OMERO.server to 5.6.3 but you will need a client that supports the TLS 1.2 protocol. Client-side, you will need omero-blitz 5.5.8 or greater client side. I would expect downloading OMERO.server 5.6.3 as a client should suffice to have the import running successfully against your OMERO.server 5.6.1.

That being said, OMERO.server 5.6.1 includes now security vulnerability and we still very highly recommend to schedule an upgrade of your server.

Best,
Sebastien

Dear Sebastien,
thanks f or the hints. Just to clarify, I am using the command line on the server for import. Is it still sufficient to update the omero-blitz as mentioned here:
https://github.com/IDR/deployment/issues/327 , although I am not using a client?

Thanks Alex

Hi Alex,

yes the steps I mentioned on the PR were the minimal set of JARs I had to replace on an IDR pilot deployment - which is currently using OMERO.server 5.6.0 - to get an successful import after upgrading OpenJDK to the new 11.0.11 release dropping support for TLS 1.0/1.1.

Note that I haven’t extensively tested the impact of only updating these two dependencies. This is why I also suggested to download a fresh OMERO.server 5.6.3 (can be alongside the OMERO.server) and use it as a client for command-line import.

Hi Sebastien,
just to give a short feedback. I replaced the two files
omero-blitz.jar
and
omero-romio.jar
in
/opt/omero/server/OMERO.server/lib/client/

with the once downloaded from the current omero.server 5.6.3.

Restarted the server and tried again a server sided command line import. It fails with the following message:

2021-04-30 11:53:01,394 2978 [ main] ERROR formats.importer.cli.CommandLineImporter - Error during import process.
Ice.ConnectionLostException: null
at IceInternal.AsyncResultI.__wait(AsyncResultI.java:276) ~[ice.jar:na]
at Ice.ObjectPrxHelperBase.end_ice_isA(ObjectPrxHelperBase.java:310) ~[ice.jar:na]
at Ice.ObjectPrxHelperBase.ice_isA(ObjectPrxHelperBase.java:92) ~[ice.jar:na]
at Ice.ObjectPrxHelperBase.ice_isA(ObjectPrxHelperBase.java:69) ~[ice.jar:na]
at Ice.ObjectPrxHelperBase.checkedCastImpl(ObjectPrxHelperBase.java:2810) ~[ice.jar:na]
at Ice.ObjectPrxHelperBase.checkedCastImpl(ObjectPrxHelperBase.java:2770) ~[ice.jar:na]
at Glacier2.RouterPrxHelper.checkedCast(RouterPrxHelper.java:1787) ~[glacier2.jar:na]
at omero.client.getRouter(client.java:889) ~[omero-blitz.jar:5.5.8]
at omero.client.createSession(client.java:810) ~[omero-blitz.jar:5.5.8]
at omero.client.joinSession(client.java:745) ~[omero-blitz.jar:5.5.8]
at ome.formats.OMEROMetadataStoreClient.initialize(OMEROMetadataStoreClient.java:764) ~[omero-blitz.jar:5.5.8]
at ome.formats.importer.ImportConfig.createStore(ImportConfig.java:381) ~[omero-blitz.jar:5.5.8]
at ome.formats.importer.cli.CommandLineImporter.(CommandLineImporter.java:162) ~[omero-blitz.jar:5.5.8]
at ome.formats.importer.cli.CommandLineImporter.main(CommandLineImporter.java:997) ~[omero-blitz.jar:5.5.8]

Maybe you have a further suggestions, otherwise I will make the full update to 5.6.3.

Thanks
Alex

Hi Alex,

no the IceConnectionLostException does not ring a bell unfortunately. The only thing I could suggest ahead of a full upgrade would be to try an import using a fresh OMERO 5.6.3 as a client i.e.

cd /opt/omero/server
wget https://downloads.openmicroscopy.org/omero/5.6.3/artifacts/OMERO.server-5.6.3-ice36-b228.zip
unzip OMERO.server-5.6.3-ice36-b228.zip
/opt/omero/server/OMERO.server-5.6.3-ice36-b228/bin/omero import

and see if that works

Dear Sebastien,
sorry to bother you again, but when I download the OMERO.server-5.6.3 as you described in your last post, it does not contain the bin subfolder. I tried this on two different machines and also a direct download.
Anything I am doing wrong?
Thanks
Alex

Yes, I just realized that my instructions are very pre- OMERO 5.6 where omero.py was bundled as part of the server artifact.

With the same set-up as above

export OMERODIR=/opt/omero/server/OMERO.server-5.6.3-ice36-b228/
/opt/omero/server/OMERO.server/bin/omero import <path_to_file>

should use the client libraries from the OMERO.server 5.6.3 bundle.

Hi Sebastien,
I exported the OMERODIR path and checked it is working, but when I issue the

/opt/omero/server/OMERO.server/bin/omero import

I get " No such file or directory" since the OMERO.server-5.6.3-ice36-b228 folder does not contain a bin subfolder and therefore no omero executable.

Thanks Alex

Ah yes, it’s quite dependent on the way you installed the server. Our Ansible roles install a little wrapper under /opt/omero/server/OMERO.server/bin/omero which is why I suggested this script.
In the general sense, you will need to activate the virtual environment used for your OMERO.server and set OMERODIR as above:

source /path/to/server/virtual/environment
export OMERODIR=/opt/omero/server/OMERO.server-5.6.3-ice36-b228/
omero import ...

Hi Omero team,

I’m experiencing the same issue but on Ubuntu 18.04 with OMERO.server-5.6.0-ice36-b136. Is the recommended course of action in this case to upgrade OMERO.server to 5.6.3?

Thanks in advance,

Ashley

Hi @ashleyvansp and welcome to the image.sc forum,

In the mid-term upgrading your OMERO.server to 5.6.3+ is definitely the recommended course of action. In addition to shipping dependencies allowing your clients to create a secure connection using the supported TLS 1.2 protocol, it includes several fixes for disclosed security vulnerabilities.

Until the server is upgraded, to fix failing imports a workaround is to use client libraries that contains the recent OMERO Java libraries against your OMERO.server 5.6.0. We are working on a documentation update and an announcement to clarify the different options.

Best,
Sebastien

Hi Sebastien,

We upgraded OMERO.server to 5.6.3 as recommended, activated the virtual environment, and set the updated OMERODIR environment variable. Like the comment above, we are also getting the following exception:

Ice.ConnectionLostException: null
	at IceInternal.AsyncResultI.__wait(AsyncResultI.java:276) ~[ice.jar:na]
	at Ice.ObjectPrxHelperBase.end_ice_isA(ObjectPrxHelperBase.java:310) ~[ice.jar:na]
	at Ice.ObjectPrxHelperBase.ice_isA(ObjectPrxHelperBase.java:92) ~[ice.jar:na]
	at Ice.ObjectPrxHelperBase.ice_isA(ObjectPrxHelperBase.java:69) ~[ice.jar:na]
	at Ice.ObjectPrxHelperBase.checkedCastImpl(ObjectPrxHelperBase.java:2810) ~[ice.jar:na]
	at Ice.ObjectPrxHelperBase.checkedCastImpl(ObjectPrxHelperBase.java:2770) ~[ice.jar:na]
	at Glacier2.RouterPrxHelper.checkedCast(RouterPrxHelper.java:1787) ~[glacier2.jar:na]
	at omero.client.getRouter(client.java:889) ~[omero-blitz.jar:5.5.8]
	at omero.client.createSession(client.java:810) ~[omero-blitz.jar:5.5.8]
	at omero.client.joinSession(client.java:745) ~[omero-blitz.jar:5.5.8]
	at ome.formats.OMEROMetadataStoreClient.initialize(OMEROMetadataStoreClient.java:764) ~[omero-blitz.jar:5.5.8]
	at ome.formats.importer.ImportConfig.createStore(ImportConfig.java:381) ~[omero-blitz.jar:5.5.8]
	at ome.formats.importer.cli.CommandLineImporter.<init>(CommandLineImporter.java:162) ~[omero-blitz.jar:5.5.8]
	at ome.formats.importer.cli.CommandLineImporter.main(CommandLineImporter.java:997) ~[omero-blitz.jar:5.5.8]

Are we missing a step in the upgrade?

Thanks,

Ashley

Hi @ashleyvansp,

thanks for the feedback. The ConnectionLostException error that both you and @alexra are experiencing is slightly confounding especially after a complete server upgrade and we have been unable to reproduce it so far. We are very keen to get this resolved properly as we would like communicate more authoritatively about the impact of the latest JDK updates on OMERO 5.6 server/clients and how to mitigate it.

A couple of immediate questions to help us moving forward:

Hi @ashleyvansp and @alexra

I am trying to narrow down the issue since we have not been able to reproduce the error on our system
Can you import using insight?

For the CLI to work omero-py 5.8.0+ is required. See https://github.com/ome/omero-py/pull/251

Do you have that version installed in the virtual env?

Cheers

Jmarie

Hi Jean-Marie,
sorry for the late answer, I was occupied with other things.
I just tried the insight import and that works.
I run the diagnostics as suggested by Sebastien, here is the output:

================================================================================
OMERO Diagnostics (admin) 5.8.3
================================================================================
Commands: java -version 11.0.11 (/usr/bin/java)
Commands: python -V 3.7.3 (/opt/omero/server/venv3/bin/python – 2 others)
Commands: icegridnode --version 3.6.5 (/opt/ice-3.6.5-0.1.0/bin/icegridnode)
Commands: icegridadmin --version 3.6.5 (/opt/ice-3.6.5-0.1.0/bin/icegridadmin)
Commands: psql --version 11.11 (/usr/bin/psql)
Commands: openssl version 1.1.1 (/usr/bin/openssl)
Server: icegridnode running
Server: Blitz-0 active (pid = 23888, enabled)
Server: DropBox inactive (disabled)
Server: FileServer inactive (disabled)
Server: Indexer-0 active (pid = 23915, enabled)
Server: MonitorServer inactive (disabled)
Server: OMERO.Glacier2 active (pid = 23921, enabled)
Server: OMERO.IceStorm active (pid = 23932, enabled)
Server: PixelData-0 active (pid = 23939, enabled)
Server: Processor-0 active (pid = 23944, enabled)
Server: Tables-0 active (pid = 23946, enabled)
Server: TestDropBox inactive (enabled)
Log dir: /opt/omero/server/OMERO.server/var/log exists
Log files: Blitz-0.log 239.4 MB errors=4 warnings=114
Log files: DropBox.log n/a
Log files: FileServer.log n/a
Log files: Indexer-0.log 11.4 MB errors=6 warnings=56
Log files: MonitorServer.log n/a
Log files: OMEROweb.lock empty
Log files: OMEROweb.log 146.7 KB errors=80 warnings=0
Log files: PixelData-0.log 3.1 MB errors=4 warnings=51
Log files: Processor-0.log 1.2 MB errors=0 warnings=3
Log files: Tables-0.log 112.2 KB errors=0 warnings=49
Log files: TestDropBox.log n/a
Log files: master.err 1.1 MB errors=0 warnings=46
Log files: master.out empty
Log files: Total size 4990.34 MB
Environment:OMERO_HOME=(unset)
Environment:OMERODIR=/opt/omero/server/OMERO.server
Environment:OMERO_NODE=(unset)
Environment:OMERO_MASTER=(unset)
Environment:OMERO_USERDIR=(unset)
Environment:OMERO_TMPDIR=(unset)
Environment:PATH=/opt/omero/server/venv3/bin:/opt/ice-3.6.5-0.1.0/bin:/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games
Environment:PYTHONPATH=(unset)
Environment:ICE_HOME=/opt/ice-3.6.5-0.1.0
Environment:LD_LIBRARY_PATH=(unset)
Environment:DYLD_LIBRARY_PATH=(unset)
OMERO SSL port:4064
OMERO TCP port:4063
OMERO data dir:’/OMERO’ Exists? True Is writable? True
OMERO temp dir:’/home/omero/omero/tmp’ Exists? True Is writable? True (Size: 0)
JVM settings: Blitz-{index} -Xmx5058m -XX:MaxPermSize=1g -XX:+IgnoreUnrecognizedVMOptions JVM settings: Indexer-{index} -Xmx3372m -XX:MaxPermSize=1g -XX:+IgnoreUnrecognizedVMOptions
JVM settings: PixelData-{index} -Xmx5058m -XX:MaxPermSize=1g -XX:+IgnoreUnrecognizedVMOptions JVM settings: Repository-{index} -Xmx3372m -XX:MaxPermSize=1g -XX:+IgnoreUnrecognizedVMOptions
Jar: lib/server/formats-api.jar Bio-Formats API 6.3.1 13 December 2019 e355a853c5768721711cb9b29c3a27561539c4e4
Jar: lib/server/formats-bsd.jar BSD Bio-Formats readers and writers 6.3.1 13 December 2019 e355a853c5768721711cb9b29c3a27561539c4e4
Jar: lib/server/formats-gpl.jar Bio-Formats library 6.3.1 13 December 2019 e355a853c5768721711cb9b29c3a27561539c4e4
Jar: lib/server/ome-codecs.jar OME Codecs 0.2.5 13 August 2019 1a8b147d5673b975e14f33d78a2be886fbaf0e20
Jar: lib/server/ome-common.jar OME Common Java 6.0.4 21 October 2019 650939cfa026e33d2f38c1f56c74715dfb44b974
Jar: lib/server/ome-jai.jar OME JAI 0.1.0 28 June 2017 96ed34bf59f5ba3b51e3d60e342f30962a46c292
Jar: lib/server/ome-mdbtools.jar MDB Tools (Java port) 5.3.2 7 August 2018 68ffca2a95750cbb96f0d11785851aa4a554c0a4
Jar: lib/server/ome-poi.jar OME POI 5.3.3 6 August 2018 3887f4b2b21e195fa76ec4378858f6278aed5dcd
Jar: lib/server/ome-xml.jar OME XML library 6.0.1 9 May 2019 4d5b2e68d178de967d53100a1726b447726282cd
Jar: lib/server/omero-blitz.jar jar 5.5.6
Jar: lib/server/omero-common.jar jar 5.5.5
Jar: lib/server/omero-gateway.jar jar 5.6.3
Jar: lib/server/omero-model.jar jar 5.5.5
Jar: lib/server/omero-renderer.jar jar 5.5.5
Jar: lib/server/omero-romio.jar jar 5.5.5
Jar: lib/server/omero-server.jar jar 5.5.6

Here is the output from the omero config get

omero.data.dir=/OMERO
omero.db.name=omero_database
omero.db.pass=********
omero.db.poolsize=500
omero.db.user=omero_db_user
omero.glacier2.IceSSL.Ciphers=HIGH:ADH:@SECLEVEL=0
omero.web.apps=[“omero_figure”, “omero_iviewer”]
omero.web.caches={“default”: {“BACKEND”: “django_redis.cache.RedisCache”,“LOCATION”: “redis://127.0.0.1:6379/0”}}
omero.web.open_with=[[“Image viewer”, “webgateway”, {“supported_objects”: [“image”], “script_url”: “webclient/javascript/ome.openwith_viewer.js”}], [“omero_figure”, “new_figure”, {“supported_objects”: [“images”], “target”: “_blank”, “label”: “OMERO.figure”}], [“omero_iviewer”, “omero_iviewer_index”, {“supported_objects”: [“images”, “dataset”, “well”], “script_url”: “omero_iviewer/openwith.js”, “label”: “OMERO.iviewer”}]]
omero.web.public.enabled=True
omero.web.public.get_only=true
omero.web.public.password=********
omero.web.public.server_id=1
omero.web.public.url_filter=^/(webadmin/myphoto/|webclient/(?!(script_ui|ome_tiff|figure_script))|webgateway/(?!(archived_files|download_as))|iviewer|api)
omero.web.public.user=student
omero.web.session_engine=django.contrib.sessions.backends.cache
omero.web.ui.top_links=[[“Data”, “webindex”, {“title”: “Browse Data via Projects, Tags etc”}], [“History”, “history”, {“title”: “History”}], [“Help”, “https://help.openmicroscopy.org/”, {“title”: “Open OMERO user guide in a new tab”, “target”: “new”}], [“Figure”, “figure_index”, {“title”: “Open Figure in new tab”, “target”: “_blank”}]]
omero.web.viewer.view=omero_iviewer.views.index

I have not installed the certificate extension. I will do that soon.

I will try the CLI import and extract the timepoints from the Blitz-0.log

Thanks
Alex

Hi @j.burel and @s.besson,

Thanks for your commitment to resolving this error.

We have not configured omero-certificates yet. The results of admin diagnostics are:

================================================================================
OMERO Diagnostics (admin) 5.9.2
================================================================================
        
Commands:   java -version                  11.0.11   (/usr/bin/java)
Commands:   python -V                      3.6.9     (/home/ubuntu/prog/omero/venv_server/bin/python)
Commands:   icegridnode --version          3.6.5     (/opt/ice-3.6.5-0.3.0/bin/icegridnode)
Commands:   icegridadmin --version         3.6.5     (/opt/ice-3.6.5-0.3.0/bin/icegridadmin)
Commands:   psql --version                 10.15     (/usr/bin/psql)
Commands:   openssl version                1.1.111   (/usr/bin/openssl)

Server:     icegridnode                    running
Server:     Blitz-0                        active (pid = 1509, enabled)
Server:     DropBox                        inactive (disabled)
Server:     FileServer                     inactive (disabled)
Server:     Indexer-0                      active (pid = 1557, enabled)
Server:     MonitorServer                  inactive (disabled)
Server:     OMERO.Glacier2                 active (pid = 1559, enabled)
Server:     OMERO.IceStorm                 active (pid = 1576, enabled)
Server:     PixelData-0                    active (pid = 1564, enabled)
Server:     Processor-0                    active (pid = 1568, enabled)
Server:     Tables-0                       inactive (disabled)
Server:     TestDropBox                    inactive (enabled)

Log dir:    /home/ubuntu/prog/omero/OMERO.server/var/log exists
Log files:  Blitz-0.log                    6.6 MB        errors=4    warnings=10  
Log files:  DropBox.log                    n/a
Log files:  FileServer.log                 n/a
Log files:  Indexer-0.log                  49.8 KB       errors=0    warnings=2   
Log files:  MonitorServer.log              n/a
Log files:  OMEROweb.lock                  empty
Log files:  OMEROweb.log                   10.2 KB       errors=0    warnings=53  
Log files:  PixelData-0.log                344.5 KB      errors=21   warnings=25  
Log files:  Processor-0.log                137.1 KB     
Log files:  Tables-0.log                   n/a
Log files:  TestDropBox.log                n/a
Log files:  master.err                     2.9 KB       
Log files:  master.out                     empty
Log files:  Total size                     7.11 MB


Environment:OMERO_HOME=(unset)             
Environment:OMERODIR=/home/ubuntu/prog/omero/OMERO.server 
Environment:OMERO_NODE=(unset)             
Environment:OMERO_MASTER=(unset)           
Environment:OMERO_USERDIR=(unset)          
Environment:OMERO_TMPDIR=(unset)           
Environment:PATH=/home/ubuntu/prog/omero/venv_server/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin:/home/ubuntu/prog/n/bin:/opt/ice-3.6.5-0.3.0/bin:/home/ubuntu/prog/omero/OMERO.insight/bin:/home/ubuntu/prog/omero/OMERO.server/bin 
Environment:PYTHONPATH=(unset)             
Environment:ICE_HOME=/opt/ice-3.6.5-0.3.0  
Environment:LD_LIBRARY_PATH=:/opt/ice-3.6.5-0.3.0/lib64:/opt/ice-3.6.5-0.3.0/lib 
Environment:DYLD_LIBRARY_PATH=(unset)      

OMERO SSL port:4064                           
OMERO TCP port:4063                           
OMERO data dir:'/home/ubuntu/omero/data'      Exists? True	Is writable? True
OMERO temp dir:'/home/ubuntu/omero/tmp'       Exists? True	Is writable? True   (Size: 0)

JVM settings: Blitz-${index}                -Xmx14400m -XX:MaxPermSize=1g -XX:+IgnoreUnrecognizedVMOptions
JVM settings: Indexer-${index}              -Xmx14400m -XX:MaxPermSize=1g -XX:+IgnoreUnrecognizedVMOptions
JVM settings: PixelData-${index}            -Xmx14400m -XX:MaxPermSize=1g -XX:+IgnoreUnrecognizedVMOptions
JVM settings: Repository-${index}           -Xmx14400m -XX:MaxPermSize=1g -XX:+IgnoreUnrecognizedVMOptions

Jar:        lib/server/formats-api.jar     Bio-Formats API	6.5.1	7 July 2020	6f50e4d52c9d96112635fd8b2dde737f31041cf0
Jar:        lib/server/formats-bsd.jar     BSD Bio-Formats readers and writers	6.5.1	7 July 2020	6f50e4d52c9d96112635fd8b2dde737f31041cf0
Jar:        lib/server/formats-gpl.jar     Bio-Formats library	6.5.1	7 July 2020	6f50e4d52c9d96112635fd8b2dde737f31041cf0
Jar:        lib/server/ome-codecs.jar      OME Codecs	0.3.0	3 March 2020	8287f33d3bff3d08a9925fa45e0b225e27d71fe0
Jar:        lib/server/ome-common.jar      OME Common Java	6.0.4	21 October 2019	650939cfa026e33d2f38c1f56c74715dfb44b974
Jar:        lib/server/ome-jai.jar         OME JAI	0.1.0	28 June 2017	96ed34bf59f5ba3b51e3d60e342f30962a46c292
Jar:        lib/server/ome-mdbtools.jar    MDB Tools (Java port)	5.3.2	7 August 2018	68ffca2a95750cbb96f0d11785851aa4a554c0a4
Jar:        lib/server/ome-poi.jar         OME POI	5.3.3	6 August 2018	3887f4b2b21e195fa76ec4378858f6278aed5dcd
Jar:        lib/server/ome-xml.jar         OME XML library	6.1.0	7 April 2020	8f490f5987062978fafe77a3e35f7bd24d211281
Jar:        lib/server/omero-blitz.jar     jar	5.5.8		
Jar:        lib/server/omero-common.jar    jar	5.5.7		
Jar:        lib/server/omero-gateway.jar   jar	5.6.5		
Jar:        lib/server/omero-model.jar     jar	5.6.2		
Jar:        lib/server/omero-renderer.jar  jar	5.5.7		
Jar:        lib/server/omero-romio.jar     jar	5.6.2		
Jar:        lib/server/omero-server.jar    jar	5.6.1

The config is:

omero.data.dir=/home/ubuntu/omero/data
omero.db.name=omero_from_backup
omero.db.pass=********
omero.db.poolsize=290
omero.db.user=ubuntu
omero.glacier2.IceSSL.Ciphers=HIGH:ADH:@SECLEVEL=0
omero.jvmcfg.percent=90
omero.jvmcfg.system_memory=16000
omero.threads.background_threads=100
omero.threads.max_threads=270
omero.web.application_server=wsgi-tcp
omero.web.application_server.max_requests=500
omero.web.apps=["corsheaders", "aimviewer", "omero_iviewer"]
omero.web.cors_origin_allow_all=False
omero.web.debug=false
omero.web.login_logo=/static/img/banner.png
omero.web.middleware=[{"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"}, {"index": 0, "class": "whitenoise.middleware.WhiteNoiseMiddleware"}, {"index": 0.5, "class": "corsheaders.middleware.CorsMiddleware"}, {"index": 10, "class": "corsheaders.middleware.CorsPostCsrfMiddleware"}]
omero.web.ome_seadragon.images_cache.driver=redis
omero.web.open_with=[["Image viewer", "webgateway", {"supported_objects": ["image"], "script_url": "webclient/javascript/ome.openwith_viewer.js"}], ["AIM annotator", "aimviewer", {"supported_objects": ["image"], "script_url": "aimviewer/openwith_viewer.js"}]]
omero.web.viewer.view=aimviewer.views.annotator
omero.web.wsgi_workers=13

Our log file is attached, please see time stamps at 2021-05-06 15:43 - I did an import at that time that produced the ConnectionLostException.
Blitz-0.log.txt (6.4 MB)

As for the venv version, running omero --version shows /home/ubuntu/prog/omero/venv_server/bin/omero 5.9.2.

Kindly,

Ashley

Sorry I forgot to post my omero.py version:
5.8.3
Thanks
Alex