All the Lync server 2013 environments I’ve deployed so far is giving Event ID 21054 from LS Address Book Server once a day. It also happens when you run Update-CsAdressBook.
I wondered what it was, and found it in the release notes for Lync Server 2013. Turns out that the issue can be safely ignored as long as the update is successful. You can also check the replication by running
Debug-csAddressBookReplication -Poolfqdn <Pool FQDN for which the event was generated>
which should give you an output like this:
As long as “Objects not indexed that should be” and “Abandoned Objects” are zero, the database is okay.
Also, if using SCOM, the Key Health Indicator (KHI) “Address Book Users Correctly Indexed” should be turned off for the pool.
I had a weird problem with an 2007R2 installation last week. The addressbook had stopped working. I checked all the normal errors, certificates and IIS on the FE, but everything seemed to be just fine. The addressbook files were created, and I could download all files in the browser. Everything seemed to be normal, except that the clients were giving the error about not being able to download the addressbook.
After a bit of searching the internets, I came across this. Seems that there was some new functionality added to IE8 where it refuses the certificate if the CRL is unreachable.
The solution is either to fix the CRL, or to uncheck “Check for server certificate revocation” under advanced settings in >IE8.