QSnap on UNIX - How To

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Unix File System iDataAgents

• Mount the COW Cache partition
• Configure a CXBF Device in Volume Explorer
• Deconfigure a CXBF Device in Volume Explorer
• Test a CXBF Device
• Use a Disk that has been Newly Added to a Client
• Change a Disk Label
• Enable QSnap on a Subclient

• Mount the COW Cache partition
• Configure a CXBF Device in Volume Explorer
• Edit the Mapping File for RAW Devices (for Oracle Volumes only)
• Deconfigure a CXBF Device in Volume Explorer
• Test a CXBF Device
• Use a Newly Configured CXBF Device (RAW Devices) (for Oracle Volumes only)
• Use a Newly Configured CXBF Device (File System) (for Oracle Volumes only)
• Use a Disk that has been Newly Added to a Client
• Change a Disk Label

CVSnaptool for UNIX

• Display All CXBF Devices
• Display All Snapshots
• Get CXBF Device Information
• Stop and Delete a CXBF Device on AIX
• Stop and Delete a CXBF Device on Linux
• Defunc and Delete a CXBF Device on Solaris

Mount the COW Cache partition

When installing the CXBF block filter driver, you were asked to specify a mount point for the copy-on-write cache. Use the example below to mount the partition.

To mount the COW Cache partition:

When you have selected an appropriate volume, mount it to the previously specified mount point using a command similar to the following:

mount /dev/cxbf/dsk/c1t1d1s1 /<mount_point>

Where:

<mount_point> is the mount point you specified during the installation of the CXBF driver.

Configure a CXBF Device in Volume Explorer

Use the following procedure to create CXBF devices using Volume Explorer.

Before You Begin

• If you encounter errors while configuring or deconfiguring CXBF devices on the client, go to /cvd.log on the client for more detailed information concerning the error.

Required Capability: See Capabilities and Permitted Actions

To create a CXBF device:

1. From the Tools menu in the CommCell Console, select Control Panel; or (if applicable), go to the Subclient Properties (Content) tab for your agent.
2. Click or double-click Volume Explorer and then click Yes at the warning prompt.
3. Select the host connected to the volume you want to configure.
4. Right-click the volume and select Configure cxbf device which opens the Submit Configure Request dialog box.
5. The volume path and name are displayed. It is strongly recommended you do not change the extent size for the volume.

   The default value for extent size is 4096. The minimum value is 128; the maximum value is 524288. The value is based on block size; to convert to bytes, multiply by 512bytes. Examples: 128 x 512bytes = 64KB; 524288 x 512bytes = 256MB For Image Level on Linux the value must be power of 2. In general, smaller values are better for small files and larger values for large files.

6. Option available only on Solaris: Enable persistence, if desired.

7. If you want the CXBF device to be automatically mounted after rebooting, you can select the Add to VFS tab option (you are asked to select Unmount Volume before configuration). This option is only selectable if you are configuring a volume that is mounted to regular device.
8. Click Ok to create the CXBF device.

Edit the Mapping File for RAW Devices

Oracle uses an environment variable called DBCA_RAW_CONFIG, and mapping file that tells the Oracle database application where to create data files, redo files and control files. DBCA_RAW_CONFIG is the variable indicating path of mapping file.

The mapping file must be modified to point to the CXBF devices created for the RAW devices.

To edit the mapping file:

1. Open the mapping file.
2. Replace the RAW devices with the appropriate CXBF devices. For example:

   System=/dev/rdsk/c1t0d2s1

   Change to:

   System=/dev/cxbf/rdsk/c1t0d2s1

3. Ensure the permissions for the devices are set to the Oracle user and Oracle group:

   chown Oracle:dba /dev/cxbf/rdsk/c1t1d1s1

   chmod 600 /dev/cxbf/rdsk/c1t0d2s1

4. Start the Oracle database.

Deconfigure a CXBF Device in Volume Explorer

Use the following procedure to deconfigure CXBF devices using Volume Explorer.

Before You Begin

• If a CXBF device on AIX was configured using Volume Explorer (where the CXBF device was added to /etc/filesystems), be sure to mount the CXBF device before you deconfigure it. If an unmounted CXBF device on AIX is deconfigured using Volume Explorer, the /etc/filesystems system file will be out of synchronization with the actual file system configuration.

  If /etc/filesystems and the actual file system configuration get out of synchronization, a manual edit of /etc/filesystems is required to correct the inconsistencies. Remove the cxbf entry and uncomment the original entry (that is, remove "*Galaxy" from the beginning of each line).

• If you encounter errors while configuring or deconfiguring CXBF devices on the client, go to /cvd.log on the client for more detailed information concerning the error.

Required Capability: See Capabilities and Permitted Actions

To deconfigure a CXBF device:

1. From the Tools menu in the CommCell Console, select Control Panel; or (if applicable), go to the Subclient Properties (Content) tab for your agent.
2. Click or double-click Volume Explorer and then click Yes at the warning prompt.
3. Select the host connected to the volume you want to configure.
4. Right-click the volume and select Deconfigure cxbf device.
5. Click Ok to deconfigure the cxbf device.

Enable QSnap on a Subclient

Related Topics:

• Subclients - SAN iDataAgents
• Subclients - Windows/Unix/Macintosh File Systems and Microsoft Data Protection Manager iDataAgent
• QSnap for the Unix File System iDataAgent
• QSnap for the Windows File System iDataAgent
• Things to Consider when Creating and Configuring File System Subclients

Before You Begin

• Review QSnap for the Windows File System iDataAgent and QSnap for the Unix File System iDataAgent.
• For Unix File System iDataAgents or Windows File System iDataAgents, also review Things to Consider when Creating and Configuring File System Subclients.

Required Capability: See Capabilities and Permitted Actions

To enable QSnap on a subclient:

1. From the CommCell Browser, right-click the subclient that you want to back up, and choose Properties.
2. For Unix File System iDataAgents or Windows File System iDataAgents, from the General tab, select the Use QSnap checkbox.
3. Click OK. Your next backup will use QSnap.

Test a CXBF Device

Use this procedure to test a CXBF device to see if the driver has successfully attached.

To test the CXBF device:

1. Log on to the client computer as root.
2. Depending on your operating system, type one of the following commands:
   • For AIX: lsdev | grep cxbf
   • For Linux: lsmod | grep cxbf
   • For Solaris: modinfo | grep cxbf
3. If the CXBF driver was attached successfully the command will return the unique identifier of the driver. For example:
   • For AIX: cxbf0 Available N/A
   • For Linux: cxbf 132200 2
   • For Solaris: 236 781f8000 c13d 234 1 cxbf (cxbf 0.1)
4. In the event that the driver did not attach successfully, do the following:
   • For AIX:
     • Execute the remdev -dl cxbf0 command
     • Execute the mkdev -c cxbf -s lvdd -t cxbf command
     • Run the lsdev | grep cxbf command again to ensure that the driver is attached
   • For Linux:
     • Execute the rmmod cxbf command
     • Execute the insmod /lib/modules/2.6.18-92.el5/extra/cxbf.ko command
     • Run the lsmod | grep cxbf command again to ensure that the driver is attached
   • For Solaris:
     • Execute the rem_drv cxbf command
     • Execute the add_drv cxbf command
     • Run the modinfo | grep cxbf command again to ensure that the driver is attached

Use a Newly Configured CXBF Device (RAW Devices)

For the Quick Recovery Agent and Image Level iDataAgents, if the Oracle instance has data files residing on a raw partition, soft links need to be re-established after creating the raw CXBF devices.

For example, if an Oracle volume is linked as:

data1.dbf -> dev/rdsk/c1t1d1s1

To create the links:

1. Shut down the Oracle database.
2. Remove the link:

   rm data1.dbf

3. After installing the CXBF driver, re-establish the link:

   ln -s /dev/cxbf/rdsk/c1t1d1s1

4. Ensure the permissions for the devices are set to the Oracle user and Oracle group:

   chown Oracle:dba /dev/cxbf/rdsk/c1t1d1s1

5. Start the Oracle database.

During Quick Recovery on the QR Agent, the soft links will automatically be associated with the recovery volume. This is analogous to automatically switching the mount points between file system volumes during recovery.

Use a Newly Configured CXBF Device (File System)

If the selected disk contains an existing file system that is mounted, then the disk will need to be unmounted and mounted on the CXBF device. (All data will be preserved.) For example, if two Oracle volumes were mounted as:

/dev/dsk/c1t1d1s1 /ora_data
/dev/dsk/c2t1d1s1 /ora_logs

Required Capability: See Capabilities and Permitted Actions

To mount them as CXBF devices:

1. Shut down the Oracle database.
2. Unmount the volumes:

   umount /ora_data
   umount /ora_logs

3. Configure the volumes as CXBF devices using Volume Explorer.
4. After installing the CXBF driver, mount the same volumes as CXBF devices using Volume Explorer:

   mount /dev/cxbf/dsk/c1t1d1s1 /ora_data
   mount /dev/cxbf/dsk/c2t1d1s1 /ora_logs

   After mounting volumes as CXBF devices, do not also mount them as ordinary Solaris devices using the dev/dsk path; this might cause a system panic.

5. Give ownership of the devices to Oracle:

   chown Oracle:dba /ora_data
   chown Oracle:dba /dev/cxbf/dsk/c1t1d1s1
   chown Oracle:dba /ora_logs
   chown Oracle:dba /dev/cxbf/dsk/c2t1d1s1

6. Start the Oracle database.

Display All CXBF Devices

Use the CVSnap Tool to display all CXBF devices.

To display all CXBF devices:

1. From the command line, type one of the following, depending on your operating system, and press Enter:

   • For Solaris: /usr/sbin/cvsnap
   • For AIX: /sbin/cvsnap
   • For Linux: /sbin/cvsnap
2. At the cvsnap> prompt, type show (on Solaris) or show_filters (on AIX or Linux) and press Enter.

   Sample output:

   No of bf devices 7
   c1t0d26s0
   c1t0d26s1
   c1t0d26s3
   c1t0d26s4
   c1t0d26s5
   c1t0d26s6
   c1t0d26s7

3. To exit, at the cvsnap> prompt, type quit and press Enter.

Display All Snapshots

Use the CVSnap Tool to display all snapshots on the computer.

To display all snapshots:

1. From the command line, type one of the following, depending on your operating system, and press Enter:

   • For Solaris: /usr/sbin/cvsnap
   • For AIX: /sbin/cvsnap
   • For Linux: /sbin/cvsnap
2. At the cvsnap> prompt, type show_snaps press Enter.
3. To exit, at the cvsnap> prompt, type quit and press Enter.

Get CXBF Device Information

Use the CVSnap Tool to obtain CXBF device information.

To get CXBF device information:

1. From the command line, type one of the following, depending on your operating system, and press Enter:

   • For Solaris: /usr/sbin/cvsnap
   • For AIX: /sbin/cvsnap
   • For Linux: /sbin/cvsnap
2. At the cvsnap> prompt, type one of the following, depending on your operating system, and press Enter:
   • getinfo device=<deviceID>
   • getinfo minor=<minor number for device>
   • getinfo bfminor=<bfminor number for device>
3. To exit, at the cvsnap> prompt, type quit and press Enter.

Stop and Delete a CXBF Device on AIX

Use the CVSnap Tool to stop and delete a CXBF filter.

To stop and delete a CXBF device:

1. From the command line, type the following command and press Enter.

   /sbin/cvsnap

2. At the cvsnap> prompt, type show_filters and press Enter.

   All the available CXBF filters will be displayed and from this list you can get the filter number which is the number appended with CXBF.

   For example:

   cvsnap>show_filters

   Sample output:

   /dev/cxbf/cxbf1/blk
   /dev/cxbf/cxbf3/blk
   /dev/cxbf/cxbf4/blk

   Here, there are three filters with filter numbers 1,3, and 4.

3. At the cvsnap> prompt, type stop_filter minor=<filter_minor_number> and press Enter.

   For example:

   stop_filter minor=1

   Sample output:

   Stopping CXBF node over:
   minor=1

4. At the cvsnap> prompt, type delete_filter_minor=0 and press Enter.
5. To exit, at the cvsnap> prompt, type quit and press Enter.
6. Next, the cxbf-bootscript1.rc and cxbf-bootscript2.rc files in /sbin need to be edited. These files are based on CXBF devices present, and are automatically generated every time a new CXBF device is detected. Edit these two files to remove the entries corresponding to the device you just deleted.
7. Verify that the device you just deleted no longer appears, using the procedure detailed in Display All CXBF Devices.

Stop and Delete a CXBF Device on Linux

Use the CVSnap Tool to stop and delete a CXBF filter.

To stop and delete a CXBF device:

1. From the command line, type the following command and press Enter.

   /sbin/cvsnap

2. At the cvsnap> prompt, type show_filters and press Enter.

   All the available CXBF filters will be displayed and from this list you can get the filter number which is the number appended with CXBF.

   For example:

   cvsnap>show_filters

   Sample output:

   /dev/cxbf/cxbf0
   /dev/cxbf/cxbf1

   Here, there are two filters with filter numbers 0 and 1.

3. At the cvsnap> prompt, type stop bfminor=<filter_number> and press Enter.

   For example:

   stop bfminor=0

   Sample output:

   Stopping CXBF node:
   minor=0

4. At the cvsnap> prompt, type delete bfminor=0 and press Enter.
5. To exit, at the cvsnap> prompt, type quit and press Enter.
6. Next, the cxbf-bootscript1.rc and cxbf-bootscript2.rc files in /sbin need to be edited. These files are based on CXBF devices present, and are automatically generated every time a new CXBF device is detected. Edit these two files to remove the entries corresponding to the device you just deleted.
7. Verify that the device you just deleted no longer appears, using the procedure detailed in Display All CXBF Devices.

Defunc and Delete a CXBF Device on Solaris

Use the CVSnap Tool to defunc and delete a CXBF device.

To defunc and delete a CXBF device:

1. From the command line, type the following command and press Enter.

   /usr/sbin/cvsnap

2. At the cvsnap> prompt, type defunc device=<deviceID> and press Enter.

   For example:

   defunc device=c1t0d6s0

   Sample output:

   defunc device=c1t0d6s0
   device c1t0d6s0 marked defunct.

3. At the cvsnap> prompt, type delete device=c1t0d6s0 and press Enter.
4. To exit, at the cvsnap> prompt, type quit and press Enter.
5. Next, the cxbf-bootscript1.rc and cxbf-bootscript2.rc files in /usr/sbin need to be edited. These files are based on CXBF devices present, and are automatically generated every time a new CXBF device is detected. Edit these two files to remove the entries corresponding to the device you just deleted.
6. Verify that the device you just deleted no longer appears, using the procedure detailed in Display All CXBF Devices.

Use a Disk that has been Newly Added to a Client

When new disks are added to a client, and have been labeled, verify that they can be seen. (If not, edit the sd.conf file as shown below.) Then, use Volume Explorer to detect the newly added disks and create cxbf devices on all the volumes of the newly added disk(s).

To edit the sd.conf file:

1. Log on to the client computer as root.
2. Navigate to the /kernel/drv/ directory.
3. Edit the file as vi sd.conf. The file will need to be modified if the target is beyond 15 and LUN is greater than 7. The following is an example of the sd.conf file:

   name="sd" class="scsi" target=0 lun=0 to target=15 lun=7

   You will need to add more entries if required by your hardware configuration.

   The maximum range of target is 0-255 and for each target LUN the range is 0-255.

   It is strongly recommended that you do not edit the file unless required.

4. See Configure a CXBF Devices in Volume Explorer to configure the volume.

Change a Disk Label

When the disk label has changed, for example, after changing sizes of the partitions/slices, the following procedure needs to be followed to see the new CXBF devices with the correct/updated sizes.

Required Capability: See Capabilities and Permitted Actions

To update the CXBF devices:

1. Unmount, deconfigure, and delete the CXBF devices related to that disk, using Volume Explorer.
2. Change the disk label.
3. Detect, configure, and mount the devices using Volume Explorer.

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