Re: Changing Query behavior based on local vs. remote context?

I discovered this when I was a network admin/dba many years ago. We had a business network and a process control network that had to be splittable for political reasons. We had an ethernet bridge set up that we could unplug to isolate the systems. I was setting up Replication (SQL 6.0/6.5, I think) between two servers. The both had FDDI interfaces , but there was the ethernet bridge between them. They negotiated large frame sizes since they were both on FDDI, not considering that the equipment in the middle couldn't pass that big a packet. Whatever genius designed the netotiation protocol didn't bother to test and see if an actual large packet could make it through. Drove me buggy troubleshooting it. Test queries worked. Ping never failed. Drives mapped. Then replication would fail to sync. I eventually found the issue and limited the packet size on the publisher/distributor and never had another problem.

--
Geoff N. Hiten
Senior SQL Infrastructure Consultant
Microsoft SQL Server MVP





"Erland Sommarskog" <esquel@xxxxxxxxxxxxx> wrote in message news:Xns998F55155F70Yazorman@xxxxxxxxxxxx
Geoff N. Hiten (SQLCraftsman@xxxxxxxxx) writes:
Sounds like larger network packets are getting dropped. Some bridges that
do not do packet splitting can cause this.

Keith's description reminds me of a very weird error that a formed DSL
provider of mine had. I was mainly reading my after a holiday in SSH2
connection to a Unix account. And that worked fine. But then I got the
idea to look at some web site, but I could not access it. Tried another.
Did not work. A third one. Eventually I tried running lynx from the Unix
account. And that hung too! But I could open a new connection and read my
mail.

Finally I came around to put a very short text file on my web site, and
sure enough, this page did turn up in the browser. So I concluded they
had an error where split packets got lost, but as long as the packets
were small, things worked.



(The reason this provider is a former provider, is simply because I moved
to a new flat, and they could not deliver DSL there.)



--
Erland Sommarskog, SQL Server MVP, esquel@xxxxxxxxxxxxx

Books Online for SQL Server 2005 at
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.

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