Manual failback commands

Manual failback commands

[Scott Dungan]

Hello all.

If we set a device to manual failback, how does one command the 
multipathd service to reinstate the path when we have decided the path 
is indeed ready to accept IO?

Thanks,

-Scott

Re: Manual failback commands

[Christophe Varoqui]

On mar., 2010-02-02 at 16:39 -0800, Scott Dungan wrote:
> Hello all.
> 
> If we set a device to manual failback, how does one command the 
> multipathd service to reinstate the path when we have decided the path 
> is indeed ready to accept IO?
> 
paths are automatically reinstated by multipathd.

The 'failback' parameter means the original path_group is not
re-activated after a switch-over to a secondary path_group.

You can force multipathd to not reinstate a path using the CLI (or
pro-actively disable it).

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

Re: Manual failback commands

[Scott Dungan]

> On mar., 2010-02-02 at 16:39 -0800, Scott Dungan wrote:
>    
>> Hello all.
>>
>> If we set a device to manual failback, how does one command the
>> multipathd service to reinstate the path when we have decided the path
>> is indeed ready to accept IO?
>>
>>      
> paths are automatically reinstated by multipathd.
>
> The 'failback' parameter means the original path_group is not
> re-activated after a switch-over to a secondary path_group.
>
> You can force multipathd to not reinstate a path using the CLI (or
> pro-actively disable it).
>    
Thanks for the clarification. I think I understand this better now. 
Would it be possible to post CLI example(s) of reinstating or disabling 
a path? I cannot seem to find such an example in documentation or other 
available resources.

Regards,

-Scott

Re: Manual failback commands

[Christophe Varoqui]

On mer., 2010-02-03 at 08:49 -0800, Scott Dungan wrote:
> > On mar., 2010-02-02 at 16:39 -0800, Scott Dungan wrote:
> >    
> >> Hello all.
> >>
> >> If we set a device to manual failback, how does one command the
> >> multipathd service to reinstate the path when we have decided the path
> >> is indeed ready to accept IO?
> >>
> >>      
> > paths are automatically reinstated by multipathd.
> >
> > The 'failback' parameter means the original path_group is not
> > re-activated after a switch-over to a secondary path_group.
> >
> > You can force multipathd to not reinstate a path using the CLI (or
> > pro-actively disable it).
> >    
> Thanks for the clarification. I think I understand this better now. 
> Would it be possible to post CLI example(s) of reinstating or disabling 
> a path? I cannot seem to find such an example in documentation or other 
> available resources.
> 

The cli has a syntax help message, accessed using 'help' or whatever
unknown keyword.

The relevant commands are:
 reinstate path $path
 fail path $path

which wrap 1/ the dm messaging to fail/resinstate a path and 2/
disable/enable the specified path checking in multipathd

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

Re: Manual failback commands

[Scott Dungan]

> The cli has a syntax help message, accessed using 'help' or whatever
> unknown keyword.
>
> The relevant commands are:
>   reinstate path $path
>   fail path $path
>
> which wrap 1/ the dm messaging to fail/resinstate a path and 2/
> disable/enable the specified path checking in multipathd
>
>    
Thanks for your continued help. Perhaps I am using the incorrect tools. 
Neither the 'multipath' command or the interactive mode of the 
multipathd daemon (multipath -k) have any of those directives documented 
under the 'help' listing, nor do they respond to them when I use them as 
you specify above. What CLI command are you using with those directives? 
Like:

%cli_command% reinstate path $path

-Scott

Re: Manual failback commands

[Christophe Varoqui]

On mer., 2010-02-03 at 09:44 -0800, Scott Dungan wrote:
> > The cli has a syntax help message, accessed using 'help' or whatever
> > unknown keyword.
> >
> > The relevant commands are:
> >   reinstate path $path
> >   fail path $path
> >
> > which wrap 1/ the dm messaging to fail/resinstate a path and 2/
> > disable/enable the specified path checking in multipathd
> >
> >    
> Thanks for your continued help. Perhaps I am using the incorrect tools. 
> Neither the 'multipath' command or the interactive mode of the 
> multipathd daemon (multipath -k) have any of those directives documented 
> under the 'help' listing, nor do they respond to them when I use them as 
> you specify above. What CLI command are you using with those directives? 
> Like:
> 
> %cli_command% reinstate path $path
> 
'multipathd -khelp' on most distro-shipped multipath-tools.
'multipathd help' is also possible with upstream.

Re: Manual failback commands

[Scott Dungan]

On 2/3/2010 11:33 AM, Christophe Varoqui wrote:
> On mer., 2010-02-03 at 09:44 -0800, Scott Dungan wrote:
>    
>>> The cli has a syntax help message, accessed using 'help' or whatever
>>> unknown keyword.
>>>
>>> The relevant commands are:
>>>    reinstate path $path
>>>    fail path $path
>>>
>>> which wrap 1/ the dm messaging to fail/resinstate a path and 2/
>>> disable/enable the specified path checking in multipathd
>>>
>>>
>>>        
>> Thanks for your continued help. Perhaps I am using the incorrect tools.
>> Neither the 'multipath' command or the interactive mode of the
>> multipathd daemon (multipath -k) have any of those directives documented
>> under the 'help' listing, nor do they respond to them when I use them as
>> you specify above. What CLI command are you using with those directives?
>> Like:
>>
>> %cli_command% reinstate path $path
>>
>>      
> 'multipathd -khelp' on most distro-shipped multipath-tools.
> 'multipathd help' is also possible with upstream.
>
> --
> dm-devel mailing list
> dm-devel@redhat.com
> https://www.redhat.com/mailman/listinfo/dm-devel
>
>    
Yes, I understand that. If I run 'multipathd -k' and then help, these 
are the commands that are listed:

      list|show paths
      list|show maps
      add path $path
      remove|del path $path
      add map $map
      remove|del map $map
      switch|switchgroup map $map group $group
      dump pathvec
      reconfigure
      disablequeueing map $map
      restorequeueing map $map


Where are the 'reinstate path' or 'fail path' directives you mention in 
this thread? In case this is a version issue, we are running with 
version device-mapper-multipath-0.4.7-30.el5_4.4. What version are you 
running where the 'reinstate path' or 'fail path' directives are listed 
in help or otherwise function?

-Scott

Re: Manual failback commands

[Scott Dungan]

On 2/3/2010 11:55 AM, Scott Dungan wrote:
> Yes, I understand that. If I run 'multipathd -k' and then help, these 
> are the commands that are listed:
>
>      list|show paths
>      list|show maps
>      add path $path
>      remove|del path $path
>      add map $map
>      remove|del map $map
>      switch|switchgroup map $map group $group
>      dump pathvec
>      reconfigure
>      disablequeueing map $map
>      restorequeueing map $map
>
>
> Where are the 'reinstate path' or 'fail path' directives you mention 
> in this thread? In case this is a version issue, we are running with 
> version device-mapper-multipath-0.4.7-30.el5_4.4. What version are you 
> running where the 'reinstate path' or 'fail path' directives are 
> listed in help or otherwise function?
>
> -Scott
>
> -- 
> dm-devel mailing list
> dm-devel@redhat.com
> https://www.redhat.com/mailman/listinfo/dm-devel
>
It looks like I have answered my own question. I was confused about 
which version we were running. I was testing against version 4.5. Those 
commands are not available in version 4.5 (RHEL 4.8). They are present 
in version 4.7 (RHEL 5.x).

Thanks for your help.

-Scott

-- 

Scott A Dungan
Systems Administrator
GPS Division
California Institute of Technology
Phone: (626) 395-3170
Fax:   (626) 585-1917