improvement(events): add rack aware policy event

[juliayakovlev]

Add RackAwarePolicy cassandra-stress log event when a test runs with multiple availability zone.

2025-01-01 09:53:27.896: (CassandraStressLogEvent Severity.NORMAL) period_type=one-time event_id=db556fb0-db45-42a1-8068-7abd224b3997: type=RackAwarePolicy regex=Using provided rack name '.+' for RackAwareRoundRobinPolicy line_number=143 node=Node longevity-cdc-100gb-4h-rack-awa-loader-node-82ae1911-1 [34.245.189.8 | 10.4.7.144] (rack: 0)
INFO  [main] 2025-01-01 09:53:27,319 RackAwareRoundRobinPolicy.java:114 - Using provided rack name '1b' for RackAwareRoundRobinPolicy

Task: https://github.com/scylladb/qa-tasks/issues/1819

Testing

• multi AZ longevity

Printed in an email:

Test details
Test: longevity_test.LongevityTest.test_custom_time
Build number: 6
Backend: aws: ['eu-west-1']
Kernel version: 5.15.0-1073-aws
Test-id: ee42c9a3-fe4a-4f96-bfe8-b30e8fc1cc72
[Link to argus](https://argus.scylladb.com/tests/scylla-cluster-tests/ee42c9a3-fe4a-4f96-bfe8-b30e8fc1cc72)
Start time: 2025-01-02 11:21:43
End time: 2025-01-02 11:38:23
Started by user: julia.yakovlev
Cassandra-stress uses shared-aware driver
Cassandra-stress uses RackAwareRoundRobinPolicy with provided rack name

PR pre-checks (self review)

• I added the relevant backport labels
• I didn't leave commented-out/debugging code

Reminders

• Add New configuration option and document them (in sdcm/sct_config.py)
• Add unit tests to cover my changes (under unit-test/ folder)
• Update the Readme/doc folder relevant to this change (if needed)

[fruch]

@juliayakovlev

maybe we should have something like is_shard_awareness_driver too ? to report to email or Argus this information ?

[juliayakovlev]

@juliayakovlev

maybe we should have something like is_shard_awareness_driver too ? to report to email or Argus this information ?

Added. In Argus we print in Resources tab info about node's rack. Where do you suggest to report with is_rack_aware_policy property? In the Detailed tab?

[juliayakovlev]

@soyacz @fruch please, review

[fruch]

LGTM

[fruch]

@juliayakovlev

maybe we should have something like is_shard_awareness_driver too ? to report to email or Argus this information ?

Added. In Argus we print in Resources tab info about node's rack. Where do you suggest to report with is_rack_aware_policy property? In the Detailed tab?

We later would discuss with @k0machi and @soyacz where this should go in Argus

[soyacz]

LGTM,
Is there a way to validate is RackAaware c-s works e.g. by verification in monitoring?

[juliayakovlev]

LGTM, Is there a way to validate is RackAaware c-s works e.g. by verification in monitoring?

@soyacz
unfortunately we do not have any metrics that report about rack