[OpenAFS] how to change openafs server ip address?

[TIARA System Man]

dear guys,

i have openafs servers in 140.109.x.x and 117.108.x.x networks. those
two networks are in different places. one of my openafs server in
117.108.x.x have to be relocated to 140.109.x.x network. if the
117.108.x.x place is no longer available, how do i change the ip
address of 117.108.x.x afs server to 140.109.x.x?

i found vos changeaddr command
(http://www.openafs.org/pages/doc/AdminReference/auarf257.htm).
however, i still don't know how to change server ip address?

vos changeaddr -oldaddr 117.108.x.x  -newaddr 140.109.x.x

should i change ip address first or use above command first? this
openafs server is a file server machine and a vlserver. could anyone
teach me the standard operation of changing afs server ip address.
thank you.

best, sam

-- 
Sam Tseng
Academia Sinica
Institute of Astronomy and Astrophysics
Tel: +886-2-3365-2200 ext 742
Fax: +886-2-2367-7849