ICMP Problem

usmany · ‎09-15-2004

Guys I need assistance on about (ICMP)...

I disabled ip mask-reply from my ser0/0 interface, will that reduce responding to ICMP from other host? and what will that amount to?

I want to know the consequnce of my action to that please.

spremkumar · ‎09-15-2004

hi

this is wht i got from cisco ..

http://www.cisco.com/en/US/products/sw/iosswrel/ps1835/products_configuration_guide_chapter09186a00800ae127.html#13891

hope this may be help u out..

regds

usmany · ‎09-15-2004

Thanks.

Richard Burts · ‎09-15-2004

It would help if you could be specific about what you did.

If you configured on some interface(s) no ip mask-reply and did not make any other changes, then the answer is that your router will not respond to the ICMP request for mask information. So in absolute terms it may reduce your router responding to ICMP. But ICMP mask request is a fairly uncommon message, so I think the reduction will be very little.

ICMP has many capabilities and many kinds of messages. Mask Request and Mask Reply is one small part of what ICMP does. So if the only thing you did was to suppress mask reply then I think the consequence of your change is minimal.

HTH

Rick

HTH

Rick

usmany · ‎09-15-2004

what i want to do is to reject ICMP from host that wanted to hack my network or over-load the network with that (icmp).

i discovered that my network time-to-time use to be slow and i view that something is transmitting almost 90% of my total bandwidth making us not to even ping our service providers' interface connect to our network, or making respond from the providers network to timed out completely and when i troubleshooted all my devices including servers. I found no trace of virus but my serial interface is transmitting more. so what will be the problem?

i suspect icmp from other host trying to over load us and when i used that command (no ip mask-reply) to the ser0/0 interface, we started to ping and browse. so i want to know what will be the consequence of my action of disabling replying to icmp from any host.... will that deny us (my network) to perform any taxk?