Subject: Re: [Bug 4554] New: /proc/net/route missing info for 127.0.0.1/8

From: Arnaldo Carvalho de Melo <[email-masked]>
Date: Tue, 3 May 2005 19:55:15 -0300

On 5/3/05, Stephen Hemminger <[email-masked]> wrote:
> On Wed, 04 May 2005 00:41:01 +0200
> Patrick McHardy <[email-masked]> wrote:
> 
> > > Distribution: CentOS 4 (RHEL4)
> > > Hardware Environment: i686
> > > Problem Description:
> > > cat /proc/net/route is missing information for 127.0.0.1/8 network (lo
> > > interface).  On 2.4 kernels, this info was present (just checked on an old RH7.3
> > > machine).  It seems to be missing on 2.6 kernels.  Bug?  Feature?  Omission?
> >
> > 2.4.30 doesn't show it:
> >
> > # route -n
> > Destination     Gateway         Genmask         Flags Metric Ref    Use
> > Iface
> > 172.16.0.0      0.0.0.0         255.255.0.0     U     0      0        0 eth0
> >
> > And I'd be surprised if it did, it doesn't include other routes
> > from the local table.
> >
> > Regards
> > Patrick
> 
> It shows up on our 2.4.18 system, probably it got lost in the fib/seq_printf
> conversion.
> 
> $ /sbin/route -n
> Kernel IP routing table
> Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
> 192.168.159.0   172.20.4.11     255.255.255.0   UG    0      0        0 eth2
> 172.20.0.0      0.0.0.0         255.255.0.0     U     0      0        0 eth2
> 127.0.0.0       0.0.0.0         255.0.0.0       U     0      0        0 lo
> 0.0.0.0         172.20.0.1      0.0.0.0         UG    0      0        0 eth2

[root@toy acme]# route -n
Tabela de Roteamento IP do Kernel
Destino         Roteador        MáscaraGen.    Opções Métrica Ref   Uso Iface
192.168.1.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0
172.20.0.0      0.0.0.0         255.255.0.0     U     0      0        0 tun0
127.0.0.0       0.0.0.0         255.0.0.0       U     0      0        0 lo
0.0.0.0         192.168.1.2     0.0.0.0         UG    0      0        0 eth0
[root@toy acme]# uname -r
2.6.11-77124cl
[root@toy acme]#

[root@toy acme]# ip r s
192.168.1.0/24 dev eth0  proto kernel  scope link  src 192.168.1.192
172.20.0.0/16 dev tun0  proto kernel  scope link  src 172.20.0.1
127.0.0.0/8 dev lo  scope link
default via 192.168.1.2 dev eth0
[root@toy acme]#

[root@toy acme]# cat /proc/net/route
Iface   Destination     Gateway         Flags   RefCnt  Use     Metric
 Mask            MTU     Window  IRTT
eth0    0001A8C0        00000000        0001    0       0       0     
 00FFFFFF        0       0       0
tun0    000014AC        00000000        0001    0       0       0     
 0000FFFF        0       0       0
lo      0000007F        00000000        0001    0       0       0     
 000000FF        0       0       0
eth0    00000000        0201A8C0        0003    0       0       0     
 00000000        0       0       0
[root@toy acme]#

No problems here.

- Arnaldo