swap partition missing?

[Paul Howarth]

Hongwei Li wrote:
>>Hongwei Li wrote:
>>
>>>>Hongwei Li wrote:
>>>
>>>
>>>>>Yes, it works.  Thank you very much!  Now, I have questions:
>>>>>
>>>>>1. What's the use of mkswap -L SWAP-hda7 /dev/hda7? I don't see any
>>>>>effect?
>>>>
>>>>It *should* be setting the "filesystem label" of the partition to
>>>>"SWAP-hda7" so that mkswap can find it by name rather than being needed
>>>>to be told where exactly the swap partition is.
>>>>
>>>>
>>>>
>>>>>2. When I put the original entry back to /etc/fstab as:
>>>>>LABEL=SWAP-hda7         swap     swap    defaults 0 0
>>>>>
>>>>>it does not work again.  I have to put /dev/hda7 in it.  How to let the
>>>>>original entry work -- the above mkswap ... does not have effect?
>>>>
>>>>Was your system swapping to that partition at the time you did the
>>>>mkswap?
>>>>
>>>>
>>>>>Why do we need those LABEL=... in fstab?
>>>>
>>>>The idea is that labels should be less of a moving target than device
>>>>names. For example, lots of people found that their SATA drives moved
>>>
>>>>from being /dev/hdX to /dev/sdX fairly recently. Labelling filesystems
>>>
>>>>means that the OS can find them no matter what the device name is. This
>>>>isn't without its problems (e.g. when moving disks between machines,
>>>>resulting in multiple partitions with the same labels), but that's why
>>>>they're there.
>>>>
>>>>Labels for swap partitions are discussed at:
>>>>https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=127892
>>>>
>>>>Paul.
>>>>
>>>>--
>>>
>>>
>>>Here is what I did in the order:
>>>
>>># swapoff -a
>>>
>>># mkswap -L SWAP-hda7 /dev/hda7
>>>Setting up swapspace version 1, size = 2097410 kB
>>>
>>># vi /etc/fstab
>>>(set:
>>>LABEL=SWAP-hda7         swap     swap    defaults        0 0
>>>)
>>>
>>># swapon -a
>>>swapon: cannot find the device for LABEL=SWAP-hda7
>>
>>I just tried this on my own FC3 box and it worked. Is this the only swap
>>partition in use on your machine?
>>
>>Paul.
>>
>>--
> 
> 
> Yes, it is.

I don't know what it is then (unless perhaps you made a typo in the 
commands, though I doubt that since they appear to have been 
cut-and-pasted), but at least you have the workaround of the /dev/hda7 
entry in fstab.

Paul.