broadcast issues with Windows 2000 servers

[simmo]

Hi,

we have a scenario with 30 Win2K servers. Currently they are split into 2 VLANS, but due to some routing issues that I won't go into here, we are considering putting them all in a single VLAN. We are worried about broadcast traffic becoming a serious issue, and I would like some feedback from people on what number of servers is considered a safe limit in this sort of environment, and if anyone has any real-world experiences of such.

Thanks.....MS.

[ali-franks]

Mark,

Firstly, must say I'm not a server guy!!

But, I recently installed some routers on the end of 64k circuits that had a server on one end. The server techies had some probs getting the PC's at the far end to see the server, so I debugged IP packets and found a coupl of things.

1. They were trying to get Active Dir working and fumbled it a bit but in the meantime I could see loads of NetBIOS name-service broadcasts on the link, so they disabled NetBIOS over TCP/IP (can't remeber if they had to do it on the clients as well) and I applied an ACL on the Ethernet port to block it anyway!

2. There was no web access involved here, but a hell of a lot of traffic was generated from the server trying to contact the root DNS servers via UDP 53. When it was getting no reply, it was trying to ping them! So they had to remove the root DNS server addresses from the Win2k server.

We all know routers are not supposed to pass broadcasts but the 1600's in this scenario were more than happy to do so, especially over the ISDN backup.

HTH

Ali