ICMP redirects

ICMP redirects

Post by Alun Saunder » Wed, 04 Mar 1998 04:00:00



Hi,

I have a Linux box set up as a default router to my Windows 95 machine. It
has a number of static routes defined as follows

netstat-rn
Destination     Gateway         Genmask         Flags Metric Ref Use
Iface
192.168.1.0     0.0.0.0         255.255.255.0   U     0      0        9 eth0
192.168.2.0     0.0.0.0         255.255.255.0   U     0      0        0 eth1
192.168.3.0     192.168.1.201   255.255.255.0   UG    0      0        2 eth0
127.0.0.0       0.0.0.0         255.0.0.0       U     0      0        1 lo

The 192.168.3 subnet is reachable only via another machine (192.168.1.201, a
Vines server !) that is also acting as an IP router.

On my Win'95 machine I see that I am getting ICMP redirects (presumably)
from the Linux machine which puts routes to the hosts on the 192.168.3 net
into my routing table. I would have expected these redirects to be subnet
redirects, but instead I am getting a new host route in my routing tables
for *every* host on the 192.168.3 subnet that I contact.

Am I missing something here or does Linux only do host level redirects ???

Alun Saunders
AMSYS, Veldhoven,  Netherlands

 
 
 

1. 1.3.x: ICMP redirect ignored, bug or feature ?

Since installing the 1.3.x kernels I get hundreds of messages in
/usr/adm/messages telling me that a redirect from our routers IP number
has been ignored by eth0 (the Linux 3com network card). I know that the 3com
router advertises itself as the default route on this segment but somehow
the new Linux kernels won't accept this ICMP redirection as of 1.3.x ??

-------------------
W.R. de Kler

2. basic approach ?

3. ICMP Redirects

4. USR Robotics Caller ID

5. ICMP Redirect

6. full screen X window?

7. Problem with ICMP redirect

8. Where is the 256M DLM memory segment?

9. What is a ICMP Redirect

10. kernel: ICMP redirect from <gateway-ip>

11. These "ICMP redirect from xxx.xxx.xxx.xxx" errors

12. Disabling ICMP redirects.

13. ICMP redirect messages in syslog