nanog mailing list archives

Re: Filtering Source Addresses on gw-internet

From: Greg Ketell <gketell () cisco com>
Date: Tue, 12 Aug 1997 13:06:26 -0700

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At 03:05 PM 8/12/97 -0400, C. Jon Larsen wrote:

gw-internet#show access-lists 120
Extended IP access list 120
   deny   ip any 10.0.0.0 0.255.255.255 log
   deny   ip any 172.16.0.0 0.0.255.255 log
   deny   ip any 172.17.0.0 0.0.255.255 log
   deny   ip any 192.168.0.0 0.0.255.255 log
   permit ip a.b.c.0 0.0.0.255 any (27429 matches)
   deny   ip any any log


Line 2 and 3 could be replaced by
deny ip any 172.16.0.0 0.15.255.255 log

which would block all 172.16.0.0-172.31.0.0 as per the RFC.

You might also want to block 127.0.0.0.

GK

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Current thread:

Filtering Source Addresses on gw-internet C. Jon Larsen (Aug 12)
- Re: Filtering Source Addresses on gw-internet Greg Ketell (Aug 12)
  - Re: Filtering Source Addresses on gw-internet C. Jon Larsen (Aug 13)
- <Possible follow-ups>
- Re: Filtering Source Addresses on gw-internet C. Jon Larsen (Aug 12)
  - Re: Filtering Source Addresses on gw-internet Jon Lewis (Aug 12)
- Re: Filtering Source Addresses on gw-internet Greg Ketell (Aug 13)
- Re: Filtering Source Addresses on gw-internet Greg Ketell (Aug 14)
  - Re: Filtering Source Addresses on gw-internet Jon Lewis (Aug 15)
    - Re: Filtering Source Addresses on gw-internet Tony Li (Aug 15)