Not enough free physical extents

[Warren griggs]

I am trying to extend /usr "on-the-fly" but when I use lvextend I get an error message saying
"lvextend: Not enough free physical extents available.
Logical volume "/dev/vg00/lvol6" could not be extended.
Failure possibly caused by strict allocation policy"

I have 1024MB available on this disk and am only trying to extend the vol by 500MB

Any ideas why this is not working?

Thanks,

Colin.

[Rita C Workman]

OK..I must assume that since your doing this 'on the fly' you really do have Online AdvanceJFS...

So let me give you a little tip...if your extending vg00 I would be willing to bet your entering the /dev/dsk/c_t_d_ at the end of your lvextend statement...don't...just enter it without this ..

lvextend -l _ _ _ /dev/vg00/lvol7

Regards,
/rcw
rcw

[Warren griggs]

The command line that I am using is...

# lvextend -L 1500 /dev/vg00/lvol6

[Rick Garland]

In using the capital L in your command you are telling it to extend by MB and I don't think you have a 1500MB disk, at least you don't say so. Use the lower case l (el) switch to the command, this will tell it to extend using extents rather that MB. If you have the default 4MB per extent and you want to increase by 500MB,
lvextend -l 125

(4)*(125)=500

[James R. Ferguson]

Hi Colin:

If you have mirrored this logical volume, it is also possible to obtain the failure in the 'lvextend' you are getting, if there is insufficient space on one of the physical disks to allocate extents and keep the primary and mirrored extents separate.

In this case, an 'lvdisplay' will show "stict" (the default) for the allocation policy. This insures that mirror copies and primary copies of the same logical volume cannot exist on the same physical volume.

If this is the case, look at the output of 'lvdisplay -v /dev/vg00/lvolX' and 'vgdisplay -v /dev/vg00' to find the number and distribution of free extents on each of the disks.

...JRF...

[Patrick Wallek · Accepted solution]

If you use the lower case l (el) in the lvextend command, then you will need to specify the TOTAL number of extents you want the logical volume to be.

Say /usr is currently 352 MB. With 4MB extents, that would be 88 extents. If you want to increase by 500 MB, to make it 852 MB or 213 extents (213 extents * 4 MB = 852 MB), then your lvextend would be: 'lvextend -l 213 /dev/vg00/lvol7'

If you wanted to use the upper case L option, then you would do an 'lvextend -L 852 /dev/vg00/lvol7'

I also agree with James, in that there may not be enough extents available on one of the disks in your mirror. That is a definite possibility as well.

[Johan Carlsson]

Hi Colin,

How full is the filesystem at this point? If it is at 100% in a bdf output it will probably be helpfull to increase a little bit at a time. Or you could delete some files in the filesystem, but of course this is usally not recommended or a preferd solution.
(Just make sure you have a valid backup!!!)

Here is a Document (KBAN00000084) which you should be able to find in the ITRC under knowledge tree.

Short is that when you perform a lvextend the command needs some space on the logical volume to perform some operations.

Hope this is of help to you.

Best Regards

Johan Carlsson

[Warren griggs]

Thanks for your help, I have sorted the problem now.

Best regards,

Colin.

[Carlos Fernandez Riera]

I think that you must change lv setings.

lvchange -C n # no contigous allocation policy.