Yesterday afternoon, one of my consumers randomly crashed/rebooted. Upon rebooting, its replication agreement with its master failed with the following error:

Unable to acquire replica: Excessive clock skew between the supplier and the consumer. Replication is aborting

I did a little bit of Google searching and found some list traffic from a few years ago. From that I derived that this replica was hosed and I would need to re-initialize it. No problem. A re-initialization didn't do anything, same error. Starting from scratch from a completely new/fresh replica produces the same result. That's when I noticed the following errors in the logs on the master.

csngen_new_csn - Warning: too much time skew (-115319 secs). Current seqnum=1

I downloaded the readNsState.py script attached to the following ticket (https://bugzilla.redhat.com/show_bug.cgi?id=233642). Running this on the master produced the following output

For replica cn=replica,cn=o\3Dpotsdam.edu,cn=mapping tree,cn=config
  len of nsstate is 40
  CSN generator state:
    Replica ID    : 6560
    Sampled Time  : 1328928777
    Time in hex   : 0x4f35d809
    Time as str   : Fri Feb 10 21:52:57 2012
    Local Offset  : 0
    Remote Offset : 261
    Seq. num      : 1
    System time   : Thu Feb  9 14:00:01 2012
    Diff in sec.  : -114776

This leads me to believe that the clock skew problem is on the master.

I am not really sure how the clock skew happened. All of these systems synchronize their clocks via a centralized time server and all the times on their clocks are correct. There are 3 or 4 other replicas that are still receiving incremental updates fine, but any attempt to add a new replica results in a failed replication agreement due to excessive clock skew.

I am writing to get a better understanding of the situation and see if there is anything to be done to resolve this. At the moment it seems as if I am caught in an unfortunate situation that will require re-initialization of my master from a back-up.

Thanks for any help that can be provided.
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