Issue 

After upgrading from Redpanda 25.2.x to Redpanda 25.3.1 , the Redpanda logs may have a lot of authentication warnings  reported for   audit_log_client 

Detail 

Lot of these messages are observed in the logs

WARN  2025-12-02 14:49:57,842 [shard 0:main] kafka/client - audit_log_client - cluster.cc:180 - Failed to dispatch metadata request - { node: 39 }, { error_code: sasl_authentication_failed [58] }: SASL authentication failed: security: Invalid credentials

Audit logging  feature is working okay , but the Redpanda logs will continue to be spammed with these WARN messages

You may also seen an increase on metric  redpanda_rpc_request_errors_total
sum(rate(redpanda_rpc_request_errors_total{}[$__rate_interval])) by ([[aggr_criteria]])

 
This issue was identified as a Redpanda bug : CORE-14903

 

Resolution/Workaround 

Audit logging is working okay in this scenario,  but to get round log message spam, 
one additional rolling restart of the brokers after the upgrade will clear this state.

Redpanda bug : CORE-14903