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CERN Batch Service Changelog

The purpose of this space is to keep track of significant changes in CERN's batch infrastructure and to announce planned upcoming changes that may impact users' interaction with the sytem.

Upcoming changes

Mid/End November 2025 - Submissions from AFS no longer supported with EosSubmit schedds

EosSubmit schedds were introduced in March 2025 as way to make easier for users to submit jobs consuming input files from EOS storage, or writing files to EOS storage. These schedds were marked experimental because of our limited experience with them.

While initially EosSubmit schedds also supported jobs using non-EOS (i.e. AFS) paths, this support will be now removed, since this functionality was not really useful (this can be achieved with traditional schedds), and was source of several subtle bugs in EosSubmit behaviour. Thus:

  • Mid/End November 2025: EosSubmit schedds will only accept jobs were all relevant paths are located in EOS.

For more details, please check the EosSubmit schedds documentation, which has been updated accordingly.

End of November 2025 - Stdout/err streaming from jobs no longer supported

The live streaming of the standard output and standard error produced by HTCondor jobs (requested by setting stream_output and stream_error to True in the submit file) has never worked reliably (or at all) in CERN's batch system. On the contrary, it is known to often cause problems for users.

Therefore, the following changes will be performed:

  • Mid-November 2025: CERN's schedds will warn users requesting stdout/err streaming.
  • End-November 2025: CERN's schedds will refuse jobs requesting stdout/err streaming.

Past changes

2025-10-21 - Upgrade of HTCondor access points

Upgrade of HTCondor access points (schedds) and computing elements (CEs) from v23 to v24. This upgrade should not have any impact on users. At this point, all CERN's batch infrastructure is running HTCondor v24.

2025-06-17 - Upgrade of HTCondor Central Managers

Upgrade of HTCondor Central Managers (collector, negotiator) from HTCondor v23 to v24. From this point on, only HTCondor clients with versions greater or equal to v23.0.9 or v24 can now submit jobs to the infrastructure.

2025-06-10 - Upgrade of HTCondor managed clients

Upgrade of HTCondor clients in lxplus/aiadm from v23 to v24. This upgrade may require adjustments in the usage of the HTCondor client, especially in what regards the submission of HTCondor jobs (e.g. with condor_submit), in particular:

  • The use of multiple queue statements in a single submit description file is now deprecated. This functionality is planned to be removed during the lifetime of the V24 feature series.

  • ClassAd language no longer supports unit suffixes on numeric literals (still allowed in the submit language in request_disk and request_memory, but not in arbitrary ClassAd expressions)

The upgrade also means the end of support for EL7 in centrally managed config for HTCondor clients

Refs:

Last update: November 14, 2025