modify the ifSpeed for more as only one IF

Hallo,

can i change the ifSpeed for more as only one IF in one time?
for example:

we have many vpn-channels and the ifSpeed for this virtual interfaces are 9000bit.
but real is the speed same the speed of ethernet-interface.

this 9000bit-string is just for the boot-process and set the best routing path in the first time. (2 vpn-channels on 1 ethernet, first is the main path and better ifSpeed and will be set for routing, second is the backup path and have lower ifSpeed)
after the boot-process the real ifSpeed of vpn-channels are theoretical maximum 10Mbit.

The NetfowAnalyzer read via SNMP the ifSpeed for VPN-channels, but is not real.
Now i must change the speed of so much interfaces manualy.

can i change many interfaces in one time?? now the situation is: i can set just one ifSpeed in one time.

thanks in advance and best regards

helko