unable to create snapsots on a volume

[netappnasadmin]

Hello folks,

I establish a snapmirror relation ship between a source volume of size 3.0TB to destination volume 3.5TB.

when I initialize the snapmirror process it says snapmirror aborted.

Then i started creating snapshot manually but it says no free disk space on source volume I already started increasing the size of the source volume but still it tell's me no free disknspace.

please solve my issue as i have 3 lun's are carved on source volume and it is in production.

Thanks in advance.

Naveen

[eric_barlier]

Naveen,

Can you look in "/etc/log" for snapmirror log and find an error message at the time you try to snapmirror intitialize. I assume you have not

had this working and initializing is failing, is this correct?

then please send us this, please note from wich controller I need the info, please only send for the volume in question>

source:

df -g

vol options

snap list

destination

df -g

vol options

snapmirror status -l <volume_name>

snap list

df -r

Thanks,

Eric

[netappnasadmin]

Eric,

My volume name is EV on source filer & destination filer S_EV.

source filer details:

snap list EV

working..

no snapshots exists.

> vol options EV

nosnap=off, nosnapdir=off, minra=off, no_atime_update=off, nvfail=off,

ignore_inconsistent=off, snapmirrored=off, create_ucode=on,

convert_ucode=on, maxdirsize=31457, schedsnapname=ordinal,

fs_size_fixed=off, guarantee=volume, svo_enable=off, svo_checksum=off,

svo_allow_rman=off, svo_reject_errors=off, no_i2p=off,

fractional_reserve=100, extent=off, try_first=volume_grow

df -g:

Filesystem               total       used      avail capacity  Mounted on

/vol/EV/                4183GB     3422GB      760GB      82%  /vol/EV/

/vol/EV/.snapshot          0GB        0GB        0GB     ---%  /vol/EV/.snapshot

Destination details:

df -g

I cannot see any thing about S_EV volume

snapmirror status -l S_EV

snapmirror status -l S_EV
Snapmirror is on.

Source:                 BOSNAP002:EV
Destination:            BOSNAP006:S_EV
Status:                 uninitialized

Progress:              0KB
State:                  Uninitialized
Lag:                    -
Mirror Timestamp:       -
Base Snapshot:          -
Current Transfer Type:  Initialize
Current Transfer Error: -
Contents:               -
Last Transfer Type:     -
Last Transfer Size:     -
Last Transfer Duration: -
Last Transfer From:     -

df -r

no information about S_EV

when I initialize snapmirror I get "snapmirror process aborted"

please correct me.

Thanks in Advance

naveen.

[netappnasadmin]

hello eric,

on destination vol options S_EV

volume S_EV resticted or offline options are unknown.

sorry for missing it on earlier reply.

Thanks in advance

Naveen

[eric_barlier]

Hi,

I noticed your source volume is a lot bigger than 3.0TB, its more like 4.5TB. Your destination should be the same size as a minimum.

For starters you need to online the destination volume

vol online S_EV                                                                      then you need to resize it, but before you do check you have enough size in the aggregate:

df -Ag                                                                                    look for the aggr. where S_EV is, and see that you have enough space. If you do, then run

vol size S_EV 4500g                                                               at this point you could also get a vol options and send across

vol options S_EV                                                                    Restrict the volume again

vol restrict S_EV                                                                     Snapmirror initialize:

snapmirror initialize -S BOSNAP002:EV BOSNAP006:S_EV      check status

snapmirror status -l

You should be OK at this stage. If you find that you have not got enough space you can shrink destination volume while it is online and serving

data and set the destination volume the same size. Keep in mind a volume needs to be online to have the size changed or have commands ran against it.

Also, make sure you have a /etc/snapmirror.conf file with a schedule in it.

Eric

[netappnasadmin]

Hello eric,

I increased size of the destination (S_EV) volume bigger than source volume.

Again I intialized the snapmirror again I got a error "snapmirror process was aborted"

My concern since i created LUN;s on my source volume EV do i need to make changes on

vol options EV

nosnap=off, nosnapdir=off, minra=off, no_atime_update=off, nvfail=off,

ignore_inconsistent=off, snapmirrored=off, create_ucode=on,

convert_ucode=on, maxdirsize=31457, schedsnapname=ordinal,

fs_size_fixed=off, guarantee=volume, svo_enable=off, svo_checksum=off,

svo_allow_rman=off, svo_reject_errors=off, no_i2p=off,

fractional_reserve=100, extent=off, try_first=volume_grow

do u want me to change "fractional_reserve=0" instead of 100.

Thanks

Naveen.

[cedric_renauld]

ional reserve @ 0Hi,

Your VOL are SIS or not ?

If no , you can effectivly try to made a fracttional reserve @ 0, beceause when your snapmirror is launch the first think it's do, is a snapshot, and with the Fract reserve @ 100, the snap want to take the same space of the original, if I remembre correctly, my courses ...

Anyone confirm ?

And you dont have any space to do that

So if you turn to 0 your fract reserve, be careful ! the snap can take space on vol, and your lun can have no space to write on VOL...

It's highly recommended to check very frequently the space avaiable ...

[eric_barlier]

Hi,

Can you run

df -r

on both volumes and post it here. Also, go into /etc/log/ and look for snapmirror log and get the error message that relates to this volume.

For now leave fract.reserve to what it is. Turning that on or off is a bigger decision about how you monitor space and how you use snapshots on the volume.

We use the following for our LUNs

no snap reserve

no volume guarantee

no space reservation for the LUN

this pushes all the free blocks into the aggregate and we monitor space utilization at aggr. level. that avoids us having to keep track of snap reserver, volume

space used. its simplifies everything and enables management to keep look at one graph to decide when to buy storage.

Eric

[netappnasadmin]

Hello eric,cedric,

Thanks for your support I changed fractinaol_reserve to 0% and started the snapmirror this time it got successful.

following is the message:

vol options EV

nosnap=off, nosnapdir=off, minra=off, no_atime_update=off, nvfail=off,

ignore_inconsistent=off, snapmirrored=off, create_ucode=on,

convert_ucode=on, maxdirsize=31457, schedsnapname=ordinal,

fs_size_fixed=off, guarantee=volume, svo_enable=off, svo_checksum=off,

svo_allow_rman=off, svo_reject_errors=off, no_i2p=off,

fractional_reserve=0, extent=off, try_first=volume_grow

df -r EV

df -r EV

Filesystem              kbytes       used      avail   reserved  Mounted on

/vol/EV/            4386193408 3588930688  797262720          0  /vol/EV/

/vol/EV/.snapshot            0      40644          0          0  /vol/EV/.snapshot

destination:

df -r S_EV

df -r S_EV

Filesystem              kbytes       used      avail   reserved  Mounted on

/vol/S_EV/          4386193408 3588909680  797283728          0  /vol/S_EV/

/vol/S_EV/.snapshot          0      19636          0          0  /vol/S_EV/.snapshot

> snapmirror status -l S_EV

Snapmirror is on.

Source:                 BOSNAP002:EV

Destination:            BOSNAP006:S_EV

Status:                 Idle

Progress:               -

State:                  Snapmirrored

Lag:                    00:53:20

Mirror Timestamp:       Wed Oct 14 08:01:23 EST 2009

Base Snapshot:          BOSNAP006(0101184528)_S_EV.40

Current Transfer Type:  -

Current Transfer Error: -

Contents:               Replica

Last Transfer Type:     Scheduled

Last Transfer Size:     19644 KB

Last Transfer Duration: 00:02:32

Last Transfer From:     BOSNAP002:EV

If any thing needsto be corrected please let me know

Thanks

Naveen

[eric_barlier · Accepted solution]

Hi Naveen,

If you have a LUN inside your volume and use snapshots it would be prudent to set volume autosize on. Look up the command

and see what it does. Fractional reserve is a mechanism that allows to take space upfront for the LUN so that it never runs out of space.

this has been turned off now as you know, so now you need to allow the volume to grow in case it needs to. Do you use snapshots in the volume?

Eric

[netappnasadmin]

yes eric,

I have a LUN inside the volume we monitor the volume & aggregate and delete the old snapshots in the volume,.

Thanks

Naveen.

[eric_barlier]

Hi Naveen,

So now you monitor volume AND aggregate. If you were to set volume guarantee to none you would only have to monitor aggr. space.

This is thin provisioning. Of course you need to make sure you never fill up your aggr. above 90%, or you have to move things around

and/or buy more disk space. Having snap autodelete should also help, I assume you already got snap autodelete on.

Eric

[netappnasadmin]

yes Blair, we have snap auto delete option on.

Thanks for you help.

Thanks

Naveen.