Some neat regex to parse certain messages from Kubernetes logs.
RBAC DENY Messages
Good to setup some log alerting on those messages to make sure the applications are not hammering the API servers with “bad” RBAC.
Match message (should be enough for matching):
\] RBAC DENY:
Rewriting into a comma separated list + showing occurence counts:
perl -n -e'/\] RBAC DENY: user "(.+)" groups \[(".+")\] cannot "([a-zA-Z]+)" resource "([a-zA-Z._-]+)" in namespace "([a-zA-Z-_]+)"/ && print "ns=$5,verb=$3,resource=$4,user=$1,groups=$2\n"' | sort | uniq -c