Inconsistent renews from F/O peers

Mark Sandrock sandrock at
Mon May 11 15:53:11 UTC 2015


      it sometimes happens that shortly
after obtaining an initial lease of MCLT,
(3600 seconds), some Windows clients
send a broadcast renew request that
is responded to differently by the two
failover peers.

This pre-mature renew request comes
say 3 seconds after the initial lease grant,
and the granting (primary) peer acks
the renew request with a 3597 value,
whereas the secondary peer extends
the lease to the full 24 hours by acking
the renew request with an 86,400 value.

While Windows recognizes that it now
has a 24-hour lease, the client's
switch port does not recognize
the lease extension, and the connection
is dropped an hour after the laptop
was first docked.

Although this seems incorrect behavior
on the switch'es part, the pathological
behavior of Windows renewing a lease
only 3 seconds into it, also seems wrong.

Have others seen this problematic
behavior, I wonder?

Thank you.

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