/csb/arc -- CSB online archive

2008.07.24 -- A new file system will be created to provide access to archival data that is still being used. An example would be when someone named Student leaves the lab of Professor Pi. Student has been working on projectX, and otherlab members need access to the data Student has left behind.

Student's data is in /csb/pi/student/projectX. The entire directory will be moved, so it will now reside in /csb/arc/pi/student/projectX.

Directories will be moved to /csb/arc when requested by the PI or appropriate deputy. Once a directory is moved to /csb/arc, it cannot be modified or added to.

Advantages of using /csb/arc

Historic data is protected from accidental modification or deletion.
There is a clear separation between work done by different people at different times.
Since it does not change, a single backup copy of a directory on /csb/arc can be made once. Therafter, it need not be updated.

Implementation

Performed 2008.07.25

Initially, /csb/arc will be implemented on the Winchester system, on RAID1, on the 286-GB vv6, the logical volume that formerly held /csb/am/0 and /csb/wang/0. Snapshots will be on the former /snap/qqq. At this writing, these are /dev/sdm and /dev/sdp respectively. However, device letter assignments may vary when the system is rebooted, so we will use filesystem labels in /etc/fstab.

Verify that no file systems using /dev/sdm or /dev/sdp are in /etc/mtab, and that the above-named filesystems have been removed from /etc/fstab

Use fdisk to reformat /dev/sdm and /dev/sdp into a single partition. Then:

	    mkfs.ext3 -L csbarc /dev/sdm1
	    mkfs.ext3 -L sn-arc /dev/sdp1

Create mountpoints, add to /etc/fstab, and mount the filesystems.
Problem: Entries in /etc/fstab are
```
	  LABEL=csbarc /csb/arc   ext3 defaults 1 2
	  LABEL=sn-arc /snap/arc  ext3 defaults 1 2
	  
```
Attempting to mount produces mount: special device /dev/disk/by-label/sn-arc does not exist
Apparently, the links in /dev/disk/by-label get built at system startup time. I could put in a link manually.
```
	  ds1:/dev/disk/by-label # ln -s ../../sdp1 sn-arc
	  ds1:/dev/disk/by-label # ln -s ../../sdm1 csbarc
	  
```
That seems to have worked.

Add to /etc/exports and exportfs -r.

       /csb/arc    @Core(rw,sync,mp) @Staff(rw,sync,mp) @Batch(rw,sync,mp) 
       /snap/arc   vs2p(ro,sync,mp,no_root_squash)

Add to /etc/ypfiles/amd.csb. It should be unnecessary to add to amd.snap, because the snapshot should be identical to the original, and is only there in case of catastrophic failure on RAID1.
test access from core workstations
Add to ds1 snapshot rotation file /eve/adm/winchester/rsync/rsync-fs.daily and set for 1 snapshot.

Last Modified: Friday, 25-Jul-2008 13:35:40 EDT

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