Author Archive

Transfer of DataStorageWiki to

January 13th, 2009 No comments

So after a lot of hard work over the past weekend, finally the DataStoragewiki Blog site is now transferred over to  I have explained in the previous blog why this was important (

With a bit planning and import / export of data, finally was able to move over stuff from DataStorageWiki to StorageNerve with practically zero downtime. Also realized how great it was to have FeedBurner, No outages on the RSS & ATOM feeds. The subscriber list is unaffected.

Included script on page, which would automatically forward all the users to in about 5 seconds.  But this only works with the home page forwarding (www) and not the associated URL’s.

One thing I would really like to do is automatically forwarded all the DNS queries that came over to* (any URL within the domain) to I tried to do some domain forwarding using CNAME and A Records but didn’t go anywhere.

The big problem I do see is that Google search results are all based on  and its associated URL’s, so when a user clicks on it today, they ending up with a 404 Page. In short the users that are trying to access technical data through search and are getting Page Not Found. Not sure if there is a way to fix this.

Another potential problem is it will take light years for site to be relisted again on Google and Yahoo. Since most of the blogging I do is related to technical terms, Google ranking and ratings on them is very important. With the content that is published on the pages, the current Google Page & Google Site ranking for them is pretty good. Now it will take another 6 months before the same is done for the new domain.

Again one of my purposes of blogging is to help Storage Experts throughout the world understand and compare technologies in terms of technical information and product research. With those things in mind, a search engine optimization does play a very important role with worldwide visitors that come in through search engines.

Hope as a reader you have not felt any outages with this site and your subscribed feed to this site is working okay.

I have couple of Blogs ready to be published, but will wait a few days before all the users get updated with the new site address.

Thanks for Reading and Goodluck on your Projects!!!

DataStorageWiki.COM becomes StorageNerve.COM

January 11th, 2009 No comments


As of Jan 10th 2009, will re-point to

When initially I had purchased the domain name, the idea was to truly create a WIKI site where users can come in and work on Storage docs to keep them updated. This would allow a lot of storage specialist throughout the world to centrally collaborate on upkeep of these docs. 

When the site was launched, it was more a central place for me to create and upload technical documents, but as time progressed it became more of a blogging adventure. 

The name DataStorageWiki is truly not a blogging name and I will keep it reserved in the future for the above endeavor. 

With the current blogging trends etc, its best to keep the website theme, names, etc on lines of blogging rather than WIKI. 

With that in mind I have moved the site to

For right now, all the users will automatically be re-pointed from to until the search engines etc start relisting all as This should be applicable to all the feed readers as well. 

In the mean time as goes live, I will start designing some concepts on and eventually host that site as a WIKI site. 

Hope there are no outages with this transfer……

LUN and VBUS Mapping for HP-UX

January 10th, 2009 1 comment

Here are the set of commands needed for mapping LUNS and VBUS on a HP-UX system.

Your command file should look like.

map dev XXX to dir FA:P, vbus=X, target=Y, lun=Z;

XXX is the Symmetrix device being mapped
FA is the director the device is being mapped to
P is the port on the FA
X is the virtual bus value (valid values 0-F)
Y is the target id (valid values 0-F)
Z is the lun address (valid values 0-7)

The symcfg –sid xxx list –available –address (Blog on available list of LUNS on a FA for mapping) will display LUNS above 7, but these are not valid and usable by HP-UX. 

You will have to find the next available LUN 0-7. If there are no more available addresses on any VBUS you can map a device and specify the next VBUS. This will create a new VBUS and adds the available LUNS to it.

In the case where the HP-UX host is shared on the FA with another host type and heterogeneous port sharing is being used, it is only necessary to specify a LUN address. 

You will need to enable the Volume Set Address (V) flag on the FA or it will end up in error. The LUN address specified should be 3 digits, containing the required VBUS, target and LUN values. This LUN address will be interpreted as VBUS, target and LUN when the HP-UX host logs into the Symmetrix.

HP-UX Volume (Disk) and File system functions

January 10th, 2009 No comments

Here are some HP-UX Commands that will come handy with Volumes and Filesystem.

Search for attached disk

ioscan -fnC disk

Initialize a disk for use with LVM

pvcreate -f /dev/rdsk/c0t1d0

Create the device structure needed for a new volume group.

cd /dev
mkdir vgdata
cd vgdata
mknod group c 64 0x010000

Create volume group vgdata

vgcreate vgdata /dev/dsk/c0t1d0

{ if your expecting to use more than 16 physical disks use the -p option, range from 1 to 256 disks. }

Display volume group vgdata

vgdisplay -v vg01

Add another disk to volume group

pvcreate -f /dev/rdsk/c0t4d0

vgextend vg01 /dev/dsk/c0t4d0

Remove disk from volume group

vgreduce vg01 /dev/dsk/c0t4d0

Create a 100 MB logical volume lvdata

lvcreate -L 100 -n lvdata vgdata

newfs -F vxfs /dev/vgdata/rlvdata

Extend logical volume to 200 MB

lvextend -L 200 /dev/vgdata/lvdata

Extend file system to 200 MB
{ if you don’t have Online JFS installed volumes must be unmounted before you can extend the file system. }

fuser -ku /dev/vgdata/lvdata { kill all process that has open files on this volume. }

umount /dev/vgdata/lvdata

extendfs /data

{ for Online JFS, 200 MB / 4 MB = 50 LE; 50 x 1024 = 51200 blocks }

fsadm -F vxfs -b 51200 /data

Set largefiles to support files greater than 2GB

fsadm -F vxfs -o largefiles /data

Exporting and Importing disks across system.

1. Make the volume group unavailable

vgchange -a n /dev/vgdata

2. Export the the disk while creating a logical volume map file.

vgexport -v -m data_map vgdata

3. Disconnect the drives and move to new system.

4. Move the data_map file to the new system.

5. On the new system recreate the volume group directory

mkdir /dev/vgdata
mknod /dev/vgdata/group c 64 0x02000

6. Import the disks to the new system

vgimport -v -m data_map /dev/vgdata /dev/dsk/c2t1d0 /dev/dsk/c2t2d0

7. Enable the new volume group

vgchange -a y /dev/vgdata

8. Renaming a logical volume

/dev/vgdata/lvol1 -> /dev/vgdata/data_lv

umount /dev/vgdata/lvol1

ll /dev/vgdata/lvol1 take note of the minor ( e.g 0x010001 )
brw-r—– 1 root root 64 0x010001 Dec 31 17:59 lvol1

mknod /dev/vgdata/data_lv b 64 0x010001 create new logical volume name

mknod /dev/vgdata/rdata_lv c 64 0x010001

vi /etc/fstab { reflect the new logical volume }

mount -a

rmsf /dev/vgdata/lvol1

rmsf /dev/vgdata/rlvol1