Nexus Repo caches LDAP server authentications and authorizations for performance. The default time for this cache is 10 minutes.
If you're having problems with intermittent LDAP server authentication failures this cache timeout can be increased as a workaround. This will reduce the frequency of failures. It should be noted that this is just a bandaid, the best solution is to fix the issue with the LDAP server.
To make this change, edit $datadir/etc/nexus.properties file and add a line like this:
nexus.ldap.cache.user.timeToLive=60m
Restart Nexus Repo for this to have effect.
You can use seconds, minutes, hours, or days as units (5s, 7m, 9h, 11d).
Note: The downside to going with a very high value is that if the LDAP password for a user has changed they will not be able to log into Nexus Repo until the cache expires, or someone manually clears the LDAP cache.