Q about redundant internet feeds, multiple gateways, redhat 7

Q about redundant internet feeds, multiple gateways, redhat 7

Post by Ian Dougl » Sat, 19 May 2001 03:03:40



We have 2 available Internet connections, for redundancy, but we're
having trouble getting the second feed to work.

We have two feeds coming in on one 10baseT cable into a hub, and from
the hub we are connecting to the two network cards.

Our ifconfig setup:

eth0      Link encap:Ethernet  HWaddr 00:00:00:00:00:01  
          inet addr:1.2.3.226  Bcast:1.2.3.231  Mask:255.255.255.248
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:1914722 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2100107 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:100
          Interrupt:11 Base address:0xa800

eth2      Link encap:Ethernet  HWaddr 00:00:00:00:00:02  
          inet addr:4.5.6.226  Bcast:4.5.6.231  Mask:255.255.255.248
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:9570 errors:0 dropped:0 overruns:0 frame:0
          TX packets:51 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:100
          Interrupt:3 Base address:0xa000

Our routing table:
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref
Use Iface
4.5.6.224  0.0.0.0         255.255.255.248 U     0      0        0
eth2
1.2.3.224  0.0.0.0         255.255.255.248 U     0      0        0
eth0
0.0.0.0         1.2.3.225  0.0.0.0         UG    0      0        0
eth0

The default gateway route for the 4.5.6.224 network is SUPPOSED to be
.225, but when I try to add that route to the routing table after
removing the default to go through 1.2.3.225, I get this:

root /etc> route del -net 4.5.6.224 netmask 255.255.255.248
root /etc> route add -net 4.5.6.224 netmask 255.255.255.248 gw
4.5.6.225 eth2
SIOCADDRT: Network is unreachable
root /etc> _

So, I added the network back on the default gateway for the time
being:

root /etc> route add -net 12.146.197.224 netmask 255.255.255.248 eth2

I'm pretty low on the skill side of setting up redundant links like
this. Can someone provide any pointers on what I can try? I'm above
average in terms of other areas of Linux administration, just never
set up a second network feed like this.

RedHat 7.0, i386, 2.2.16-22

Any assistance or pointers would be greatly appreciated.

Ian Douglas

 
 
 

1. Q about redundant internet feeds, multiple gateways, redhat 7

We have 2 available Internet connections, for redundancy, but we're
having trouble getting the second feed to work.

We have two feeds coming in on one 10baseT cable into a hub, and from
the hub we are connecting to the two network cards.

Our ifconfig setup:

eth0      Link encap:Ethernet  HWaddr 00:00:00:00:00:01  
          inet addr:1.2.3.226  Bcast:1.2.3.231  Mask:255.255.255.248
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:1914722 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2100107 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:100
          Interrupt:11 Base address:0xa800

eth2      Link encap:Ethernet  HWaddr 00:00:00:00:00:02  
          inet addr:4.5.6.226  Bcast:4.5.6.231  Mask:255.255.255.248
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:9570 errors:0 dropped:0 overruns:0 frame:0
          TX packets:51 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:100
          Interrupt:3 Base address:0xa000

Our routing table:
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref
Use Iface
4.5.6.224  0.0.0.0         255.255.255.248 U     0      0        0
eth2
1.2.3.224  0.0.0.0         255.255.255.248 U     0      0        0
eth0
0.0.0.0         1.2.3.225  0.0.0.0         UG    0      0        0
eth0

The default gateway route for the 4.5.6.224 network is SUPPOSED to be
.225, but when I try to add that route to the routing table after
removing the default to go through 1.2.3.225, I get this:

root /etc> route del -net 4.5.6.224 netmask 255.255.255.248
root /etc> route add -net 4.5.6.224 netmask 255.255.255.248 gw
4.5.6.225 eth2
SIOCADDRT: Network is unreachable
root /etc> _

So, I added the network back on the default gateway for the time
being:

root /etc> route add -net 12.146.197.224 netmask 255.255.255.248 eth2

I'm pretty low on the skill side of setting up redundant links like
this. Can someone provide any pointers on what I can try? I'm above
average in terms of other areas of Linux administration, just never
set up a second network feed like this.

RedHat 7.0, i386, 2.2.16-22

Any assistance or pointers would be greatly appreciated.

Ian Douglas

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