Varyoffvg in AIX

# varyoffvg <Volume_Group> : Commad to deactivate a volume group.

When a volume group is not active the logical volume or the physical volume on the volume group could not be listed.

To overcome this issue, we can apply "-s" flag when we varyoff of the volume group, this flag is for maintenance mode. This would ensure we can still view the attributes of a volume group even though its deactivated.

# varyoffvg -s vgp
# lsvg -l vgp
vgp:
LV NAME             TYPE       LPs   PPs   PVs  LV STATE      MOUNT POINT
lvn                 ???        10    10    1    closed/syncd  N/A
loglv00             ???        1     1     1    closed/syncd  N/A
#
# lsvg -p vgp
vgp:
PV_NAME           PV STATE          TOTAL PPs   FREE PPs    FREE DISTRIBUTION
hdisk5            active            542         531         109..97..108..108..109
#

Basic Veritas Volume Manager Commands

# vxprint  -g <Disk Group> : Command shows information about a disk group.

# vxdctl mode : Command to check th status of Veritas Service.

# vxdctl stop : Command to stop the Veritas Service.

# vxconfigd -m start : Command to start the Veritas Service.

# vxinstall : Comman to initalize Veritas Volume Manager.

# vxdisksetup -i <disk_name> : Command to prepare a disk for VxVM.

# vxdiskunsetup -C <disk_name> : Command to unconfigure the disk from VxVM.

# vxdg init <DG_Name> <Disk_Name> : Command to create a Disk Group.

# vxassist -g <DG_Name> make <Volume_Name> <Size> : Command to create a logical volume.

# newfs -F vxfs /etc/vx/rdsk/<DG_Name>/<Volume_Name> : Command to format a logical volume.

Hpunix Storage Troubleshooting Command

Hi All..The post mainly foucs on how to handle storage relelated problems from the Server End.

#  cat /var/adm/syslog/syslog.log : Analyze the file to find what kind problem has been reported.

# ioscan -funC disk/tape : Command to check the status of the disk and tape and not the device is "no_hw" state.

# ioscan -funH : Command to check the status of the Hardware path from the syslog.log.

# ioscan -fun fc : Command to check the status of the FC HBA.

# fcmsutil /dev/fcd# : Command to check the status of the HBA. Status should be "online" not "Awaiting Link up"

# fcmsutil /dev/fcd# stat -s  : Command to check the statistics of the FC HBA.

# fcmsutil /dev/fcd# get remote all : Command to get all the remote ports connected to this FC HBA.

Multipath in Linux

We all know the concept of Multipathing, which is configured for redundancy purpose to ensure the L UN's from the Storage Team is always available at the server.

1) # multipath -l : Command to view the configured multipath devices.

2) # cd /proc/scsi : Location of the HBA file which contains the WWN Number. In Linux, the HBA files are stored as 0,1.... The same numbering notation reflects in the "multipath" output.

3) /etc/multipath.conf : Configuration file for multipath.

4) # multipathd -k : Command which opens the interactive console with the ">" prompt.

>show paths : Command shows all the configured multipaths.
>show maps : Command shows all mapping of LUN.
 

mksysb error while taking OS backup

# mksysb -vipX /file_system

The above is the command to take a backup of rootvg (Operating System) in AIX.

When the above command fails:

1) Need to check the size of the destination filesystem, which has to match the rootvg.

2) Need to check the # ulimit values.

3) Need to check the /etc/exclude.rootvg file.

VG Configuration and Restore in HP UX

This posts shows how to take backup of a volume group configuration and restoring.

# cd /etc/lvmconf/<vgname> : The directory by default holds the backup of all the volume group configurations.

The volume group configuration is taken whenever LVM commands are applied on the volume group.

The configuration files are always stored with the ".conf" extension.

# vgcfgbackup -f <filename.conf> <volume_group> : Command to  take back up of the volume group.

# vgcfgrestore -f <filename.conf> </dev/rdsk/c#t#d#> : Command to restore the volume group configuration on a physical volume.

The above process is applied, during a disk replacement activity. When a faulty disk is replaced in a volume group, instead of mirroring the data on a new disk we simply apply the configuration file and execute "# vgsync" command. This applies the configuration on the new disk.

Hi All, Its Time To Navigate Veritas Volume Manager.