[OpenAFS] 1.4 (fs) -> 1.5 (dafs) migration

Simon Wilkinson sxw@inf.ed.ac.uk
Fri, 20 Aug 2010 15:17:36 +0100


On 20 Aug 2010, at 15:05, G=E9mes G=E9za wrote:

> We currently have a small cell (2 db and file-servers
> (1.4.7.dfsg1-6+lenny1), ~50 volumes). But plan to move the user home
> dirs to afs resulting in >1000 volumes. Being afraid of the fs based
> startup times we decided to move to a 1.5 based dafs prior to complete
> the data migration to afs.

If you have sufficient hardware, I would urge you to perform your =
migration by using AFS's tools, rather than playing fast and loose with =
where volumes are mounted. So, bring up some dafs fileservers, and use =
vos move to migrate volumes from the 1.4 servers to the 1.5 ones. This =
has the advantage that you've got a very simple backout plan if things =
go wrong for any reason, as well as allowing you to perform a staged =
migration without any downtime.

> The data is on a Coraid SAN, so it will be
> simply unmounted from the old fileservers, and mounted to the new =
ones,
> but what operations would we need to perform on the ubik data?

If you do want to go down this route, you will need to update the VLDB =
location for every volume that has changed fileservers. vos syncvldb and =
vos syncserv should do this for you - but there will be a period of =
outage for all of your clients.

Cheers,

Simon.