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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?

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

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.

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.

Quote:

Originally Posted by jlightner (Post 3228786)

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.

Quote:

Originally Posted by Linux Newbee (Post 3228821)

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.

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

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.