unreachable 127.0.0.0/8 scope host
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From: agryppa on 12 Jun 2010 11:33 Hi, my machine (gentoo linux) lists an unreachable net address of 127.0.0.0/8 of scope host. **** localhost ~ # ip route show scope host unreachable 127.0.0.0/8 **** Some people suggested that it is the /etc/init.d/network script that is at fault, which states this: === einfo "Starting network" routeflush if [ "$RC_UNAME" = "Linux" ]; then ifconfig lo 127.0.0.1 netmask 255.0.0.0 || cr=1 route add -net 127.0.0.0 netmask 255.0.0.0 \ gw 127.0.0.1 2>/dev/null route add -net 127.0.0.0 netmask 255.0.0.0 \ gw 127.0.0.1 reject 2>/dev/null else ifconfig lo0 127.0.0.1 netmask 255.0.0.0 || cr=1 route -q add -inet 127.0.0.0 -netmask 255.0.0.0 \ 127.0.0.1 reject || cr=1 fi === The internet connection, X server, pinging of local host works fine. I would like however to figure out WHY the "unreachable" clause pops up. Here is some more information: ******** localhost# ip route show table all 192.168.1.0/24 dev br0 scope link metric 6 unreachable 127.0.0.0/8 scope host 127.0.0.0/8 via 127.0.0.1 dev lo scope link 127.0.0.0/8 via 127.0.0.1 dev lo default via 192.168.1.1 dev br0 metric 6 broadcast 192.168.1.0 dev br0 table local proto kernel scope link src 192.168.1.12 broadcast 127.255.255.255 dev lo table local proto kernel scope link src 127.0.0.1 broadcast 192.168.1.255 dev br0 table local proto kernel scope link src 192.168.1.12 local 192.168.1.12 dev br0 table local proto kernel scope host src 192.168.1.12 broadcast 127.0.0.0 dev lo table local proto kernel scope link src 127.0.0.1 local 127.0.0.1 dev lo table local proto kernel scope host src 127.0.0.1 local 127.0.0.0/8 dev lo table local proto kernel scope host src 127.0.0.1 local ::1 via :: dev lo proto none metric 0 mtu 16436 advmss 16376 hoplimit 4294967295 local fe80::211:d8ff:fe1c:89e via :: dev lo proto none metric 0 mtu 16436 advmss 16376 hoplimit 4294967295 local fe80::211:d8ff:fe1c:89e via :: dev lo proto none metric 0 mtu 16436 advmss 16376 hoplimit 4294967295 local fe80::dc7f:50ff:fe0a:2a1f via :: dev lo proto none metric 0 mtu 16436 advmss 16376 hoplimit 4294967295 fe80::/64 dev tap0 proto kernel metric 256 mtu 1500 advmss 1440 hoplimit 4294967295 fe80::/64 dev eth0 proto kernel metric 256 mtu 1500 advmss 1440 hoplimit 4294967295 fe80::/64 dev br0 proto kernel metric 256 mtu 1500 advmss 1440 hoplimit 4294967295 ff00::/8 dev tap0 metric 256 mtu 1500 advmss 1440 hoplimit 4294967295 ff00::/8 dev eth0 metric 256 mtu 1500 advmss 1440 hoplimit 4294967295 ff00::/8 dev br0 metric 256 mtu 1500 advmss 1440 hoplimit 4294967295 unreachable default dev lo table unspec proto kernel metric -1 error -101 hoplimit 255 ***** ***** localhost# ip route show table local broadcast 192.168.1.0 dev br0 proto kernel scope link src 192.168.1.12 broadcast 127.255.255.255 dev lo proto kernel scope link src 127.0.0.1 broadcast 192.168.1.255 dev br0 proto kernel scope link src 192.168.1.12 local 192.168.1.12 dev br0 proto kernel scope host src 192.168.1.12 broadcast 127.0.0.0 dev lo proto kernel scope link src 127.0.0.1 local 127.0.0.1 dev lo proto kernel scope host src 127.0.0.1 local 127.0.0.0/8 dev lo proto kernel scope host src 127.0.0.1 **** Any clues, thank you in advance Agryppa
From: Pascal Hambourg on 13 Jun 2010 06:35 Hello, agryppa a �crit : > my machine (gentoo linux) lists an unreachable net address of > 127.0.0.0/8 of scope host. > > **** > localhost ~ # ip route show scope host > unreachable 127.0.0.0/8 > **** > > Some people suggested that it is the /etc/init.d/network script that is > at fault, which states this: > > === > einfo "Starting network" > routeflush > if [ "$RC_UNAME" = "Linux" ]; then > ifconfig lo 127.0.0.1 netmask 255.0.0.0 || cr=1 > route add -net 127.0.0.0 netmask 255.0.0.0 \ > gw 127.0.0.1 2>/dev/null > route add -net 127.0.0.0 netmask 255.0.0.0 \ > gw 127.0.0.1 reject 2>/dev/null It seems that it is the last command above that creates the unreachable route. > The internet connection, X server, pinging of local host works fine. Yes, because the "local" table takes precendence over the "main" table. > localhost# ip route show table local [...] > local 127.0.0.0/8 dev lo proto kernel scope host src 127.0.0.1
From: agryppa on 13 Jun 2010 10:05 On Sun, 13 Jun 2010 12:35:53 +0200 Pascal Hambourg <boite-a-spam(a)plouf.fr.eu.org> wrote: > > === > > einfo "Starting network" > > routeflush > > if [ "$RC_UNAME" = "Linux" ]; then > > ifconfig lo 127.0.0.1 netmask 255.0.0.0 || cr=1 > > route add -net 127.0.0.0 netmask 255.0.0.0 \ > > gw 127.0.0.1 2>/dev/null > > route add -net 127.0.0.0 netmask 255.0.0.0 \ > > gw 127.0.0.1 reject 2>/dev/null > > It seems that it is the last command above that creates the > unreachable route. OK, thank you for your input on this. After the line has been commented with # sign, it seems that the issue is now fixed. But questions remain. Even before the fix the table all shows an unreachable entry at the very end. unreachable default dev lo table unspec proto kernel metric -1 error -101 hoplimit 255 Can this be somehow flushed? Agryppa
From: Pascal Hambourg on 13 Jun 2010 13:50 agryppa a �crit : > > Even before the fix the table all shows an unreachable entry at the > very end. > > unreachable default dev lo table unspec proto kernel metric -1 error -101 hoplimit 255 It is an IPv6 (note "hoplimit" which is specific to IPv6) default route which is present by default. Use -4 if you want to list only IPv4 routes. > Can this be somehow flushed? Never tried. Why would you need to do that ?
From: agryppa on 13 Jun 2010 13:48
On Sun, 13 Jun 2010 19:50:06 +0200 Pascal Hambourg <boite-a-spam(a)plouf.fr.eu.org> wrote: > > Can this be somehow flushed? > > Never tried. Why would you need to do that ? It must be my perfectionism :-) I thought it was something that needs fixing ... thank you for your expert advice I hope that a reboot won't bring the same issues, though :-) Agryppa |