Chapter 5. Known issues
This section documents known issues found in this release of Red Hat Ceph Storage.
5.1. The Cephadm utility
Cephadm does not maintain the previous OSD weight when draining an OSD
Cephadm does not maintain the previous OSD weight when draining an OSD. Due to this, if the ceph orch osd rm <osd-id> command is run and later, the OSD removal is stopped, Cephadm will not set the crush weight of the OSD back to its original value. The crush weight will remain at 0.
As a workaround, users have to manually adjust the crush weight of the OSD to its original value, or complete removal of the OSD and deploy a new one. Users should be careful when cancelling a ceph orch osd rm operation, as the crush weight of the OSD will not be returned to its original value before the removal process begins.
Repeated use of the Ceph Object Gateway realm bootstrap command causes setting the zonegroup hostname to fail
Setting the zonegroup hostnames using the Ceph Object Gateway realm bootstrap command fails when being done multiple times. Due to this, the repeated use of the Ceph Object Gateway realm bootstrap command to recreate a realm/zonegroup/zone does not work properly with zonegroup_hostnames field and the hostnames will not be set in the zonegroup.
As a workaround, set the zonegroup hostnames manually using the radosgw-admin tool. Bugzilla:2241321
5.2. Ceph Object Gateway
Processing a query on a large Parquet object causes Ceph Object gateway processes to stop
Previously, in some cases, upon processing a query on a Parquet object, that object would be read chunk after chunk and these chunks could be quite big. This would cause the Ceph Object Gateway to load a large buffer into memory that is too big for a low-end machine; especially, when Ceph Object Gateway is co-located with OSD processes, which consumes a large amount of memory. This situation would trigger the OS to kill the Ceph Object Gateway process.
As a workaround, place the Ceph Object Gateway on a separate node and as a result, more memory is left for Ceph Object gateway, enabling it to complete processing successfully.
Current RGW STS implementation does not support encryption keys larger than 1024 bytes
The current RGW STS implementation does not support encryption keys larger than 1024 bytes.
As a workaround, in Keycloak: realm settings - keys, edit the 'rsa-enc-generated' provider to have priority 90 rather than 100 and keySize as 1024 instead of 2048.
Intel QAT Acceleration for Object Compression & Encryption
Intel QuickAssist Technology (QAT) is implemented to help reduce node CPU usage and improve the performance of Ceph Object Gateway when enabling compression and encryption. In this release, QAT can only be configured on new setups (Greenfield), which is a limitation of this feature. QAT Ceph Object Gateway daemons cannot be configured in the same cluster as non-QAT (regular) Ceph Object Gateway daemons.
