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I have a server with minimal installation of CentOS6 64bit (minimal option from the installer). The bonding driver does not seem to work correctly. The output from /proc/net/bonding/bond0 is:

Bonding Mode: fault-tolerance (active-backup)
Primary Slave: None
Currently Active Slave: None
MII Status: down
MII Polling Interval (ms): 100
Up Delay (ms): 0
Down Delay (ms): 0

The as you can see there are no interfaces listed as salves. The bond driver options were configured in /etc/modprobe.d/bonding.conf as:

alias bond0 bonding
options bond0 mode=1 primary=eth0 miimon=100

Interfaces eth0 and eth4 are configured as such:



and bond0 is configured as such:


And here is output from /var/log/messages:

Dec  9 08:20:55 app2 kernel: bonding: Warning: either miimon or arp_interval and arp_ip_target module parameters must be specified, otherwise bonding will not detect link failures! see bonding.txt for details.
Dec  9 08:20:55 app2 kernel: ADDRCONF(NETDEV_UP): bond0: link is not ready
Dec  9 08:21:02 app2 kernel: ADDRCONF(NETDEV_UP): bond0: link is not ready

Can anyone offer some insight as to why the driver is failing to start? Is this a dependencies issue?

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Have you tried manually executing the ifenslave/ifconfig commands? – Zoredache Dec 9 '11 at 23:55
Just tried it now - yes it works if I do it manually. I have always configured CentOS5 as above and it always worked. – Lukasz Dec 10 '11 at 0:05
After updating the system the link came up - there must be some bug that needed fixing. Thanks for the suggestion! – Lukasz Dec 10 '11 at 0:27

Your log said:

miimon or arp_interval and arp_ip_target module parameters must be specified

Try to add lines below (you can choose your favourite options) to your ifcfg-bond0:

BONDING_OPTS='miimon=1000 mode=6'
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From my understanding bonding options must no longer be specified in the interface configuration files as this is no longer supported as of RHEL/CentOS5. – Lukasz Jan 18 '12 at 18:41
up vote 1 down vote accepted

Updating the OS with just sudo yum update fixed the issue. Not sure which part did it unfortunately.

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