The known_log_certs table is populated asynchronously via broker after a
Broker::peer_added. It may take a variable amount of time depending on where
we run this test and it has been observed flaky specifically for the
arm_debian11 task. Instead of racing, give worker-2 3 seconds for receiving
the expected table content before continuing.
Fixes#2885
By default, each certificate is now output only once per hour. This also
should work in cluster mode, where we use the net broker-table-syncing
feature to distribute the information about already seen certificates
across the entire cluster.
Log caching is also pretty configureable and can be changed using a
range of confiuration options and hooks.
Note that this is currently completely separate from X509 events
caching, which prevents duplicate parsing of X509 certificates.
