Convert F/S to later version of VXFS.. Question ....

[Brad Sheldon]

Hi  we would like to upgrade our VXFS version from a version 3 to 5.  As below is the  method for doing this.

What we woould like toknow is 

Does it interupt the F/s in any way  ie taking it momentarily offline ? 

How much space does it use ansd does it return the space once finshed ?

Is it actually worth it in the first place.

From   MAn pages..

To convert a file system from layout version three to layout version four, the file system will need enough space to accommodate the metadata.

To determine the size of the metadata, run:

/sbin/fs/vxfs/metasave -f /tmp/metasave.data /dev/vgXX/lvolX

vgXX = volume group of file system

lvolX = logical volume of file system

This would create a file called metasave.data in /tmp and this file would be the size of the free space needed to vxupgrade the file system.

The vxupgrade process should not keep the file system frozen for more than a few seconds

From our server

/data: vxfs file system version 3 layout

/backup: vxfs file system version 3 layout

we would like to go to version 5.

Sizes below.

     68592000 44986280 23433736   66% /data

 51200000 41838508 9216684   82% /backup

 THanks in advance Brad.

[Matti_Kurkela · Accepted solution]

It won't unmount the filesystem or anything like that, so applications can have files open while the upgrade is running. But as the man page says, it will cause a one-time delay of a few seconds to any on-going file operations. (Similar to experiencing a minor network hiccup while using a NFS filesystem.)

If you have some real-time software that cannot deal with its I/O operations being delayed for a few seconds, it might be necessary to schedule some application downtime for the migration.