LinuxQuestions.org
Review your favorite Linux distribution.
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Newbie
User Name
Password
Linux - Newbie This Linux forum is for members that are new to Linux.
Just starting out and have a question? If it is not in the man pages or the how-to's this is the place!

Notices


Reply
  Search this Thread
Old 06-18-2013, 10:37 AM   #1
sp_
LQ Newbie
 
Registered: Jun 2013
Posts: 2

Rep: Reputation: Disabled
Routing and redirects


Hello guys,

the network scheme is the following:

Servers in network 10.0.0.0/24 -> 10.0.0.1 (core) -> 10.0.0.2 (router with
NAT to 1.2.3.4) -> internet

As you might have guessed I have the problem with "router with NAT".
It is Debian with kernel 3.2.0-0.bpo.4-amd64.

When I try to ping/telnet/etc. I get a problem.

Example:

Server 10.0.0.123 pings 4.2.2.4:

# ping 4.2.2.4
PING 4.2.2.4 (4.2.2.4) 56(84) bytes of data.
From 10.0.0.1: icmp_seq=3 Redirect Host(New nexthop: 10.0.0.2)
From 1.2.3.4 icmp_seq=1 Destination Host Unreachable

On 10.0.0.2 we can see in ip route cache:

10.0.0.123 from 4.2.2.4 dev eth0 src 1.2.3.4
cache ipid 0x3837 rtt 75ms rttvar 60ms cwnd 10 iif eth0.635
4.2.2.4 from 10.0.0.123 tos lowdelay via 10.0.0.2 dev eth0.635 src 10.0.0.2
cache <src-direct,redirected> ipid 0x6955 iif eth0
4.2.2.4 from 10.0.0.123 via 10.0.0.2 dev eth0.635 src 10.0.0.2
cache <src-direct> ipid 0x6955 iif eth0
4.2.2.4 via 10.0.0.2 dev eth0.635 src 1.2.3.4
cache <redirected> ipid 0x6955
local 1.2.3.4 from 4.2.2.4 dev lo src 1.2.3.4
cache <local> ipid 0xec85 iif eth0.635

After that, I can flush route cache and everything works fine. When
everything works, route cache looks like this:

4.2.2.4 via 1.2.3.1 dev eth0.635 src 1.2.3.4
cache ipid 0x6955
local 1.2.3.4 from 4.2.2.4 dev lo src 1.2.3.4
cache <local> ipid 0xecb1 iif eth0.635
10.0.0.123 from 4.2.2.4 dev eth0 src 1.2.3.4
cache ipid 0x386f rtt 75ms rttvar 60ms cwnd 10 iif eth0.635
4.2.2.4 from 10.0.0.123 via 1.2.3.1 dev eth0.635 src 10.0.0.2
cache <src-direct> ipid 0x6955 iif eth0

1) When I tell 10.0.0.123 to use 10.0.0.2 as the default gateway -
everything works like a charm, without flushing the cache
2) When I have FreeBSD server as 10.0.0.2 - everything works perfectly.
Bloody route cache.

Do you have any ideas how can I solve this issue?

--
Regards,
Sergey
 
Old 06-18-2013, 03:03 PM   #2
pingu
Senior Member
 
Registered: Jul 2004
Location: Skuttunge SWEDEN
Distribution: Debian preferably
Posts: 1,350

Rep: Reputation: 127Reputation: 127
Isn't the problem just that some of your servers have wrong default gateway?
Gateway should be set to 10.0.0.2.
 
Old 06-19-2013, 01:37 AM   #3
sp_
LQ Newbie
 
Registered: Jun 2013
Posts: 2

Original Poster
Rep: Reputation: Disabled
I don't want it to be 10.0.0.2 . 10.0.0.1 is the core router and there are some specific OSPF routes on it.
 
  


Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off



Similar Threads
Thread Thread Starter Forum Replies Last Post
[SOLVED] postfixadmin redirects trscookie Linux - Server 6 03-21-2013 08:21 AM
Apache2 Redirects chrislynch8 Linux - Server 2 01-10-2012 04:09 AM
kernel icmp redirects!!! gavin2u Linux - Security 12 07-25-2008 03:26 PM
Redirects to SSL connections jrdioko Linux - Security 2 12-21-2005 09:53 PM
Apache redirects?! How rincewind Linux - Software 3 02-23-2005 03:43 PM


All times are GMT -5. The time now is 06:24 PM.

Main Menu
Advertisement
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Facebook: linuxquestions Google+: linuxquestions
Open Source Consulting | Domain Registration