eDir sync behind a firewall

[Bud Durland]

A friend called with a problem.  He's adding a new NetWare 6.5/sp8
server to his tree.  The other servers are also NW6.5/Sp8  The new
server is in a building down the road.  There is a firewall
(SmoothWall) installed at each location, and the NetWare servers are
behind them.  He's having trouble with NDS synchronization.  He tells
me that all the appropriate ports are opened on the firewalls.

If he uses DSREPAIR and requests and "Unattended Full Repair", it all
goes well.  But, a while later NDS is out of sync between the two.  He
tells me that TimeSync is working Ok and does not go out of sync. I
know he's using NTP, but I don't know how it's configured.

I'm wondering if the problem is that because the servers are behind
firewalls, they report their internal IP address (192.168.x.x), but
the packets appear to come from the external address (152.153.x.x).  I
did a cursory search of the knowledge base, but didn't see anything
that looked like it would help here.

Any help appreciated.

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