I am trying to get my routing to work on my RHEL 7 with 3 nics and 3 subnets.
I have the followig nics
DEVICE=eth0
BOOTPROTO=sttic
ONBOOT=yes
TYPE=Ethernet
USERCTL=yes
PEERDNS=yes
IPADDR=10.241.78.5
NETMASK=255.255.254.0
IPV6INIT=no
DEVICE=eth1
BOOTPROTO=static
IPADDR=10.241.74.5
NETMASK=255.255.254.0
ONBOOT=yes
TYPE=Ethernet
USERCTL=yes
PEERDNS=yes
IPV6INIT=no
DEVICE=eth2
BOOTPROTO=static
IPADDR=10.241.76.5
NETMASK=255.255.254.0
ONBOOT=yes
TYPE=Ethernet
USERCTL=yes
PEERDNS=yes
IPV6INIT=no
ip route show
10.241.74.0/23 dev eth1 proto kernel scope link src 10.241.74.5
10.241.78.0/23 dev eth0 proto kernel scope link src 10.241.78.5
10.241.76.0/23 dev eth2 proto kernel scope link src 10.241.76.5
default via 10.241.78.1 dev eth0
I have a system 10.241.74.7 behind eth1 and 10.241.76.7 behind eth2
I also have sysctl.conf setup with the following
# Controls the use of TCP syncookies
net.ipv4.tcp_syncookies = 1
# Disable netfilter on bridges.
net.bridge.bridge-nf-call-ip6tables = 0
net.bridge.bridge-nf-call-iptables = 0
net.bridge.bridge-nf-call-arptables = 0
The issue I am having is that system behind eth1 cannot reach eth2 and vice versa.
also when i initiate a ping from the .5 system
ping 10.241.74.7 -I eth2
PING 10.241.74.7 (10.241.74.7) from 10.241.76.5 eth2: 56(84) bytes of data.
From 10.241.76.5 icmp_seq=2 Destination Host Unreachable
From 10.241.76.5 icmp_seq=3 Destination Host Unreachable
From 10.241.76.5 icmp_seq=4 Destination Host Unreachable
ping 10.241.76.7 -I eth1
PING 10.241.76.7 (10.241.76.7) from 10.241.74.5 eth1: 56(84) bytes of data.
From 10.241.74.5 icmp_seq=2 Destination Host Unreachable
From 10.241.74.5 icmp_seq=3 Destination Host Unreachable
From 10.241.74.5 icmp_seq=4 Destination Host Unreachable
However, when I ping both networks from eth0 it works:
ping 10.241.76.7 -I eth0
PING 10.241.76.7 (10.241.76.7) from 10.241.78.5 eth0: 56(84) bytes of data.
64 bytes from 10.241.76.7: icmp_seq=1 ttl=64 time=0.450 ms
64 bytes from 10.241.76.7: icmp_seq=2 ttl=64 time=0.483 ms
ping 10.241.74.7 -I eth0
PING 10.241.74.7 (10.241.74.7) from 10.241.78.5 eth0: 56(84) bytes of data.
64 bytes from 10.241.74.7: icmp_seq=1 ttl=64 time=0.461 ms
64 bytes from 10.241.74.7: icmp_seq=2 ttl=64 time=0.399 ms
iptables has been flushed, so I am not sure why traffic is not passing between both networks ... there may be a routing issue?
netstat -rn
Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
10.241.74.0 0.0.0.0 255.255.254.0 U 0 0 0 eth1
10.241.78.0 0.0.0.0 255.255.254.0 U 0 0 0 eth0
10.241.76.0 0.0.0.0 255.255.254.0 U 0 0 0 eth2
0.0.0.0 10.241.78.1 0.0.0.0 UG 0 0 0 eth0
Can anyone help?