[Linux-cluster] Re: determining fsid for fs resource

[Wendy Cheng]

Terry wrote:
> On Fri, Jul 17, 2009 at 11:05 AM, Terry<td3201 at gmail.com> wrote:
>   
>> Hello,
>>
>> When I create a fs resource using redhat's luci, it is able to find
>> the fsid for a fs and life is good.  However, I am not crazy about
>> luci and would prefer to manually create the resources from the
>> command line but how do I find the fsid for a filesystem?  Here's an
>> example of a fs resource created using luci:
>>
>> <fs device="/dev/vg_data01i/lv_data01i" force_fsck="0"
>> force_unmount="1" fsid="49256" fstype="ext3" mountpoint="/data01i"
>> name="omadvnfs01-data01i"
>> options="noatime,nodiratime,data=writeback,commit=30" self_fence="0"/>
>>
>> Thanks!
>>
>>     
>
> Anyone have an idea for this?
>   

IIRC, you basically have to make up the key (fsid) by yourself. Just 
pick any number (integer) that is less then 2**32 - but make sure it is 
unique per-filesystem-per-export while NFS service is up and running. 
That is, if you plan to export the same filesystem via two export 
entries (or say, export two different directories from the very same 
filesystem) , you need two fsids. If you have x exports (regardless they 
are from the same filesystem or different filessytems) at the same time, 
you would need x fsid(s). This is mostly to do with NFS export 
(internally represented by an unsigned integer)  - don't confuse it with 
filesystem id (that is obtained via stat system call family).


-- Wendy