Stopping NetWare 5.0 from bringing up a dial-up link with multicast traffic - July 2001

NetWare 5 will multicast its presence on all interfaces by default. Due to the design of the IP stack, this behavior can cause a dial-up interface to be brought up BEFORE any traffic is actually sent. Thus, filtering is unable to prevent the link from coming up, though it can prevent traffic from being sent out. There are two ways to get around this problem - unload NCPIP.NLM or use a newer version of NCPIP.NLM with a new SET parameter.

If you unload NCPIP.NLM, you cannot log into the server using pure IP, and all server NCP communications will require IPX.

A better way would be to use the newer NCPIP.NLM contained in the OS5SP4A.EXE patch (also requires NW5SP4 to be installed). The OS5SP4A patch appears to be gone from Novell's site as of 6/14/00, but that NLM should be contained in the NW5SP5 and D51/E51SP1 service packs.

The newer NCPIP.NLM allows a SET parameter to be used to exclude or include advertisements on certain IP addresses. You may need to include all public secondary IP addresses defined, though a dial-up link usually doesn't have multiple addresses assigned.

SET NCP EXCLUDE IP ADDRESSES x.x.x.x (for the version in the service packs, use SET NCP EXCLUDE IP ADDRESSES = x.x.x.x - that is, add the = sign.)


SET NCP INCLUDE IP ADDRESSES x.x.x.x (which may be better as you should be able to list only the internal, fixed, IP addresses)

(For the version in the service packs, use SET NCP INCLUDE IP ADDRESSES = x.x.x.x - add the = sign.)

July, 2001: Another reason a dial-up link might be brought up is that BorderManager would, if configured for DNS Proxy, periodically make a DNS query for, in order to test if the configured DNS servers were up. Proxy/ACL patches from PXY017.EXE and later should stop that.

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