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Network Registrar and ICMP

We are trying to diagnose some network problems and we are seeing some traffic coming from our DNS/DHCP servers and are not sure if it is legitmate traffic. We are running Network Registrar 3.5 on Win2k servers. We are using both the DNS and DHCP functions. Both of our servers are running DHCP and each server is configured with scope/scopes for each of the LANs for which we provide DHCP service (we service around 30 school districts who get their Internet connectivity along with various other service through us).

Currently we are seeing a lot if ICMP traffic coming from our DNS/DHCP servers directed towards the districts we serve. The traffic seems to be aimed towards currently active leases and it looks to me like a large amount of the traffic from each machine is being directed towards client machines who received their leases from the other DHCP server. The "Ping address before offering" option is not active on any of our DHCP scopes.

Is this valid traffic that we have just not noticed before? If so, can someone explain to me why our NR boxes are pinging the clients? Is there a way that we can turn it off...we don't allow ICMP traffic to flow between our data center and the districts.

Thank you,

Becky

5 REPLIES
New Member

Re: Network Registrar and ICMP

Hi, that's an option (which you should disable in your case) ping host before offering an ip-address. That's a setting in the DHCP pool configuration

good luck!

Frank

New Member

Re: Network Registrar and ICMP

Thanks for the suggestion Frank, but we do already have that option turned off and are still seeing the ICMP activity.

New Member

Re: Network Registrar and ICMP

Strange, what version of CNR do you run?

New Member

Re: Network Registrar and ICMP

version 3.5

New Member

Re: Network Registrar and ICMP

Hi,

Do you have printers and pc's in the same scope or are they in seperate scopes.

Make sure that they are in seperate scopes, then the performance off your pc's will encrease.

Kind regards,

Gerwin

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