Re: stupied userspace programs or kernel bug ?

[Adam Popik]

On Wed, 7 Jul 2004, Mark Watts wrote:
That test was with 2 host network and no more hosts, routers and others...
linux#  shold have this address for virtual use only on that 
machine (loopback interface), 
netmask on all linuxboxes are same, onlny on lo was /32. When I use /24 
mask and router (routing was good until assinging ip address to loopback)
network traffic is broken about 40 icmp requests (outside local net)...
Is linux bugs ?
on same test on FreeBSD and Solaris 9 no problems (loopback is and only 
loopback)

Adam

> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
> 
> 
> > Hello ;
> > That is a problem:
> > linux#ifconfig eth0 192.168.1.1
> 
> Because you didn't specify a netmask, it defaulted to 255.255.255.0
Yes it C ...
> 
> > linux#ifconfig lo:1 192.168.1.100 netmask 255.255.255.255 up
> 
> Although you specified a tighter netmask here, the routing table is such that 
> 192.168.1.0/24 is routed out eth0, overriding the fact that 1.100 is on lo:1
> 
> I'll bet the kernel responds to the ICMP echo request because it knows it 
> holds the IP for 1.100 so it should respond, yet its outbound routing tells 
> it to respond via eth0. (somone connect me if I'm wrong)
> 
> This is probably a side effect of having two interfaces on the same subnet, 
> and having the /24 subnet higher up the routing rable than the /32 host.
> 
> I believe the behaviour you are seeing is 'by design' although the merits of 
> this have been discussed to death in the past (IIRC)
> 
> Mark.
> 
> - -- 
> Mark Watts
> Senior Systems Engineer
> QinetiQ Trusted Information Management
> Trusted Solutions and Services group
> GPG Public Key ID: 455420ED
> 
> -----BEGIN PGP SIGNATURE-----
> Version: GnuPG v1.2.4 (GNU/Linux)
> 
> iD8DBQFA7AVuBn4EFUVUIO0RAlXpAJ9I1FBUhqDDgV3Tvs53NjSM9BQq9QCeIVeu
> f4Jzs0L/LlvjOsm8CcMNoJs=
> =/jLZ
> -----END PGP SIGNATURE-----
> -
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/