LinuxQuestions.org
Support LQ: Use code LQ3 and save $3 on Domain Registration
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Networking
User Name
Password
Linux - Networking This forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.

Notices

Reply
 
Search this Thread
Old 07-25-2008, 12:26 PM   #1
Linux Newbee
LQ Newbie
 
Registered: Jul 2008
Posts: 27

Rep: Reputation: 0
Destination Host Unreachable


As user name describes me, don't have a lot of knowledge yet with red hat or linux. Setting up red hat server eth1 with static ip xxx.xxx.111.25 netmask and allowing red hat to supply broadcast. Trying to hit another server in the same subnet xxx.xxx.111.22, both have no gateways. Seperate Windows servers xxx.xxx.111.23 and .24 with same subnet and no gateway, can ping each other and xxx.xxx.111.22 but none can ping .25 my red hat.

Seems like no one can ping .25. I have turned off iptables, reslov.conf is correct as is hosts file. route displays xxx.xxx.111.0. I out of things to try.

Any suggestions?
 
Old 07-25-2008, 06:13 PM   #2
Mr. C.
Senior Member
 
Registered: Jun 2008
Posts: 2,529

Rep: Reputation: 59
What is the output of:

cat /proc/sys/net/ipv4/icmp_echo_ignore_all

If 1, make it 0.

echo 0 > /proc/sys/net/ipv4/icmp_echo_ignore_all
 
Old 07-28-2008, 08:21 AM   #3
Linux Newbee
LQ Newbie
 
Registered: Jul 2008
Posts: 27

Original Poster
Rep: Reputation: 0
comes up with a 0
 
Old 07-28-2008, 10:57 AM   #4
MensaWater
Guru
 
Registered: May 2005
Location: Atlanta Georgia USA
Distribution: Redhat (RHEL), CentOS, Fedora, Debian, FreeBSD, HP-UX, Solaris, SCO
Posts: 6,008
Blog Entries: 5

Rep: Reputation: 783Reputation: 783Reputation: 783Reputation: 783Reputation: 783Reputation: 783Reputation: 783
I've not done a config without a default gateway specified so I'm not sure its possible - I was under the impression you have to specify a default gateway even if you don't specify gateways for any other NICs.

What do "netstat -r" and "netstat -rn" show? Do you see "default" in former?

Check /etc/sysconfig/network-scripts/ifcfg-eth0 (assuming you're using eth0) and see what it has specified - maybe it defaulted to an unexpected gateway? Try adding a gateway entry there if there isn't one - use your router's IP as the gateway.
 
Old 07-28-2008, 11:39 AM   #5
Linux Newbee
LQ Newbie
 
Registered: Jul 2008
Posts: 27

Original Poster
Rep: Reputation: 0
The purpose of no gateway, there are 4 servers (2-linux, 2-2003 k) and all point to a unix netapp (storage), so unix netapp xxx.xxx.111.22 and both 2003 servers are .23.& .24 with the red hat I am trying to bring up .25. Given that they are not going out to the internet and are in the same subnet, no gateway was needed.

It can ping eth2, which was given a statice IP on another subnet, but thats it. I have tried to disable iptables, have given the dns (reslove.conf) from the 2003 servers, vi the hosts to even include xxx.xxx.111.22 with and w/o fqdn of the netapp, but no luck.

The route shows basics withe and entry for the subnet xxx.xxx.111.0 and a defualt gateway for eth2. Eth2 is conifigured to get out to the world. route -r and -rn show me same thing as route. ifcfg-eth1 shows me entries of eth1 ip,net,dev etc and all is correct.

Nic should be fine regarding drivers, otherwise it could bot be given static IP and its status remains up. I am running out of ideas.
 
Old 07-28-2008, 11:54 AM   #6
Mr. C.
Senior Member
 
Registered: Jun 2008
Posts: 2,529

Rep: Reputation: 59
Quote:
Originally Posted by jlightner View Post
I've not done a config without a default gateway specified so I'm not sure its possible - I was under the impression you have to specify a default gateway even if you don't specify gateways for any other NICs.
The default route is used only when no other specific route matches. We operating under the assumption here that each system has a route to the xxx.xxx.111.0/24 network (otherwise other system's pings would have failed).

No default route and no other specific routes means no connection to *other* networks.
 
Old 07-28-2008, 12:02 PM   #7
Mr. C.
Senior Member
 
Registered: Jun 2008
Posts: 2,529

Rep: Reputation: 59
Quote:
Originally Posted by Linux Newbee View Post
It can ping eth2, which was given a statice IP on another subnet, but thats it. I have tried to disable iptables, have given the dns (reslove.conf) from the 2003 servers, vi the hosts to even include xxx.xxx.111.22 with and w/o fqdn of the netapp, but no luck.

The route shows basics withe and entry for the subnet xxx.xxx.111.0 and a defualt gateway for eth2. Eth2 is conifigured to get out to the world. route -r and -rn show me same thing as route. ifcfg-eth1 shows me entries of eth1 ip,net,dev etc and all is correct.

Nic should be fine regarding drivers, otherwise it could bot be given static IP and its status remains up. I am running out of ideas.
Stop twiddling with /etc/hosts, /etc/resolv.conf - these have nothing to do with the ability to ping by IP address.

Ok, at this point, you are going to need to show real data, output of:

Code:
ipconfig -a
iptables -L
netstat -rn
ping othermachine's_IP
on any two machines that cannot ping each other. Nobody cares about your private LAN IPs. Also explain how all these machines are connected together.
 
Old 07-28-2008, 02:27 PM   #8
Linux Newbee
LQ Newbie
 
Registered: Jul 2008
Posts: 27

Original Poster
Rep: Reputation: 0
netstat -rn
Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
10.137.0.160 0.0.0.0 255.255.255.224 U 0 0 00 0 eth2
10.136.111.0 0.0.0.0 255.255.255.224 U 0 0 00 0 eth1
169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 00 0 eth2
0.0.0.0 0.0.0.0 10.137.0.161 U U G 00 0 eth2

ipconfig -a (only showed eth that have addressing assign to)
ifconfig -a:
eth1 Link encap:Ethernet HWaddr 00:0b:db:28:0c:0e
inet addr:10.136.111.25 Mask:255.255.255.224
UP BROADCAST MULTICAST MTU:100 METRIC:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 B) TX btyes:0 (0.0 B)
Interrupt: 20


Eth2 Link encap:Ethernet HWaddr 00:0b:db:28:0c:0e
inet addr:10.137.0.183 Mask:255.255.255.224
UP BROADCAST MULTICAST MTU:100 METRIC:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 B) TX btyes:0 (0.0 B)
Interrupt: 20


iptables -L
Code:
Chain INPUT (policy DROP)
target prot opt source destination


Chain FORWARD (policy DROP)
target prot opt source destination

Chain OUTPUT (policy DROP)
target prot opt source destination

ping
PING 10.136.111.22 (10.136.111.22) 56(84) bytes of data.
From 10.136.111.22: icmp_seq=10 Destination Host Unreachable
From 10.136.111.22icmp_seq=10 Destination Host Unreachable
From 10.136.111.22 icmp_seq=11 Destination Host Unreachable
From 10.136.111.22icmp_seq=12 Destination Host Unreachable
From 10.136.111.22 icmp_seq=14 Destination Host Unreachable
 
Old 07-28-2008, 09:22 PM   #9
Mr. C.
Senior Member
 
Registered: Jun 2008
Posts: 2,529

Rep: Reputation: 59
Your iptables default policy is to DROP for the INPUT, FORWARD, and OUTPUT chains. This makes for very uninteresting networking. Perhaps you will find ACCEPT more enjoyable.
 
  


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
destination host unreachable unikgila Linux - Networking 3 07-27-2008 07:03 AM
Destination Host Unreachable drismet Linux - Networking 1 04-25-2006 06:17 AM
destination host unreachable javpra Linux - Networking 1 03-30-2005 05:44 AM
Destination Host Unreachable danka Linux - Networking 8 01-01-2005 05:29 PM
destination host unreachable Santanu1963 Linux - Networking 7 03-09-2004 02:24 PM


All times are GMT -5. The time now is 11:15 AM.

Main Menu
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
identi.ca: @linuxquestions
Facebook: linuxquestions Google+: linuxquestions
Open Source Consulting | Domain Registration