Hello,

I have a server with 4 NICS running CentOS 5.2. I have bonded the interfaces together such that 'bond0' consists of eth0-3. This is not a problem, and works fine.

However, I now need to create a virtual interface. In a non-bonded server I would just create something like eth0:1, but with a bonded interface I am a bit confused. I have created bond0:1 simple by copying the /etc/sysconfig/network-scripts/ifcfg-bond0 file, calling it 'bond0:1' and setting the DEVICE appropriately. Then I ran 'ifup bond0:1'. The interface came up, and seems to be working okay. I have not tested yet if the bonding failover works with bond0:1 because I am doing this remotely at the moment. Tomorrow I should be able to test that.

My question is, is creating a virtual bonded interface that simple or have I missed something? Have I done this the right way, or should I instead have created a second bonded interface ('bond1') and made it consist of eth0:1, eth1:1, eth2:1 and eth3:1? Admittedly this would have involved about 8 or so interfaces in total for the server! Secondly, I added nothing to the /etc/modprobe.conf file. Should I have added anything like 'alias bond0:1 bonding'? I also did not add any static routes, yet if I use 'ping' to send packets out through the virtual IP address ping says it is doing so (so again it all seems to be working).

My concern is that while it seems to be fine at the moment, and even after rebooting, I may have missed something that will cause it to fail at some point.

For info, 'ifconfig' output shows:

============================================================= bond0 Link encap:Ethernet HWaddr xx:xx:xx:xx:xx:xx inet addr:141.163.yy.a Bcast:141.163.yy.yy Mask:255.255.255.224 inet6 addr: abcd::abcd:abcd:abcd:abcd/64 Scope:Link UP BROADCAST RUNNING MASTER MULTICAST MTU:1500 Metric:1 RX packets:88468 errors:0 dropped:0 overruns:0 frame:0 TX packets:59486 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:80654540 (76.9 MiB) TX bytes:5847688 (5.5 MiB)

bond0:1 Link encap:Ethernet HWaddr xx:xx:xx:xx:xx:xx inet addr:141.163.yy.b Bcast:141.163.yy.yy Mask:255.255.255.224 UP BROADCAST RUNNING MASTER MULTICAST MTU:1500 Metric:1 =============================================================

The 'netstat -rn' output shows:

============================================================= Kernel IP routing table Destination Gateway Genmask Flags MSS Window irtt Iface 141.163.yy.0 0.0.0.0 255.255.255.224 U 0 0 0 bond0 169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 bond0 0.0.0.0 141.163.yy.30 0.0.0.0 UG 0 0 0 bond0 =============================================================

Shouldn't 'bond0:1' appear there somewhere?

Anyone notice if I missed anything?

Thanks,

John.