How to change alias name

How to change alias name

[--[ UxBoD ]--]

Hi,

we have a situation where we need to rename a server and would also like to change the associate multipath alias.  Is this possible without restarting the whole multipath daemon and killing all our other mounted partitions ?  The server we need to work on is in a shutdown state so the associated partitions are not active.

-- 
Thanks, Phil

Re: How to change alias name

[--[ UxBoD ]--]

----- "--[ UxBoD ]--" <uxbod@splatnix.net> wrote:

> Hi,
> 
> we have a situation where we need to rename a server and would also
> like to change the associate multipath alias.  Is this possible
> without restarting the whole multipath daemon and killing all our
> other mounted partitions ?  The server we need to work on is in a
> shutdown state so the associated partitions are not active.
> 
Reading through the documentation if I do:

dmsetup -v status insguest01

I see the following with the Name being the alias.

Name:              insguest01
State:             ACTIVE
Read Ahead:        1024
Tables present:    LIVE
Open count:        4
Event number:      1
Major, minor:      253, 4
Number of targets: 1
UUID: mpath-3600144f0e2824900000049df899b0002

I can then perform the same command on each of its partitions.  If I wanted to rename this guest's devices to insguest02 would I do:

dmsetup rename insguest01 insguest02

then update /etc/multipath.conf so that the alias name reflects the new name at boot time ? and would I need to perform the same operation on all the partitions as well ?

-- 
Thanks - Phil

Re: How to change alias name

[Christophe Varoqui]

You could also start with changing the aliases in /etc/multipath.conf,
run multipath, and reload multipathd config through the CLI or restart
it altogether (which is not risky if there is no degraded situation).

Works with recent multipath tools versions at least.

regards,
cvaroqui
http://www.opensvc.com

On mer., 2010-02-03 at 14:16 +0000, --[ UxBoD ]-- wrote:
> ----- "--[ UxBoD ]--" <uxbod@splatnix.net> wrote:
> 
> > Hi,
> > 
> > we have a situation where we need to rename a server and would also
> > like to change the associate multipath alias.  Is this possible
> > without restarting the whole multipath daemon and killing all our
> > other mounted partitions ?  The server we need to work on is in a
> > shutdown state so the associated partitions are not active.
> > 
> Reading through the documentation if I do:
> 
> dmsetup -v status insguest01
> 
> I see the following with the Name being the alias.
> 
> Name:              insguest01
> State:             ACTIVE
> Read Ahead:        1024
> Tables present:    LIVE
> Open count:        4
> Event number:      1
> Major, minor:      253, 4
> Number of targets: 1
> UUID: mpath-3600144f0e2824900000049df899b0002
> 
> I can then perform the same command on each of its partitions.  If I wanted to rename this guest's devices to insguest02 would I do:
> 
> dmsetup rename insguest01 insguest02
> 
> then update /etc/multipath.conf so that the alias name reflects the new name at boot time ? and would I need to perform the same operation on all the partitions as well ?
> 

Re: How to change alias name

[--[ UxBoD ]--]

----- "Christophe Varoqui" <christophe.varoqui@opensvc.com> wrote:

> You could also start with changing the aliases in
> /etc/multipath.conf,
> run multipath, and reload multipathd config through the CLI or
> restart
> it altogether (which is not risky if there is no degraded situation).
> 
> Works with recent multipath tools versions at least.
> 
> regards,
> cvaroqui
> http://www.opensvc.com
> 
> On mer., 2010-02-03 at 14:16 +0000, --[ UxBoD ]-- wrote:
> > ----- "--[ UxBoD ]--" <uxbod@splatnix.net> wrote:
> > 
> > > Hi,
> > > 
> > > we have a situation where we need to rename a server and would
> also
> > > like to change the associate multipath alias.  Is this possible
> > > without restarting the whole multipath daemon and killing all our
> > > other mounted partitions ?  The server we need to work on is in a
> > > shutdown state so the associated partitions are not active.
> > > 
> > Reading through the documentation if I do:
> > 
> > dmsetup -v status insguest01
> > 
> > I see the following with the Name being the alias.
> > 
> > Name:              insguest01
> > State:             ACTIVE
> > Read Ahead:        1024
> > Tables present:    LIVE
> > Open count:        4
> > Event number:      1
> > Major, minor:      253, 4
> > Number of targets: 1
> > UUID: mpath-3600144f0e2824900000049df899b0002
> > 
> > I can then perform the same command on each of its partitions.  If I
> wanted to rename this guest's devices to insguest02 would I do:
> > 
> > dmsetup rename insguest01 insguest02
> > 
> > then update /etc/multipath.conf so that the alias name reflects the
> new name at boot time ? and would I need to perform the same operation
> on all the partitions as well ?
> >

Thank you Christophe.  We are using device-mapper-multipath-0.4.7-30.el5 under CentOS 5.4 X86_64 so I presume we would be okay ?

-- 
Thanks - Phil