unixway > volume management > solaris > veritas > failed boot

Replacing a failed bootdisk

In the following example, the host has a failed bootdisk (c0t0d0). Fortunately, the system is using Veritas volume manager, with a mirror at c0t1d0. The following sequence of steps can be used to restore the system to full redundancy.

System fails to boot

When the system attempts to boot, it fails to find a valid device as required by the boot-device path at device alias "disk". It then attempts to boot from the network:

screen not found.
Can't open input device.
Keyboard not present.  Using ttya for input and output.

Sun Ultra 30 UPA/PCI (UltraSPARC-II 296MHz), No Keyboard
OpenBoot 3.27, 512 MB memory installed, Serial #9377973.
Ethernet address 8:0:20:8f:18:b5, Host ID: 808f18b5.



Initializing Memory
Timeout waiting for ARP/RARP packet
Timeout waiting for ARP/RARP packet
Timeout waiting for ARP/RARP packet
...

Boot from mirror

At this point, the administrator realizes that the boot disk has failed, and queries the device aliases to find the one corresponding to the veritas mirror:

ok devalias
vx-rootmirror            /pci@1f,4000/scsi@3/disk@1,0:a
vx-rootdisk              /pci@1f,4000/scsi@3/disk@0,0:a
. . .

The administrator then boots the system from the mirror device "vx-rootmirror":

ok boot vx-rootmirror

As the system boots, Veritas volume manager detects that the volumes on the rootdisk are not accessible, and detaches those plexes from the root volumes. In spite of this, the system is able to boot cleanly from the mirror device with no operator action required.

ok boot vx-rootmirror
Boot device: /pci@1f,4000/scsi@3/disk@1,0:a  File and args: 
SunOS Release 5.8 Version Generic_108528-16 64-bit
Copyright 1983-2001 Sun Microsystems, Inc.  All rights reserved.
Starting VxVM restore daemon...
VxVM starting in boot mode...
/usr/sbin/prtconf: getexecname() failed
vxvm:vxconfigd: WARNING: Detaching plex rootvol-01 from volume rootvol
vxvm:vxconfigd: WARNING: Disk rootdisk in group rootdg: Disk device not found
configuring IPv4 interfaces: hme0.
Hostname: pegasus
VxVM starting special volumes ( swapvol rootvol var )...
VxVM general startup...
dumpadm: no swap devices could be configured as the dump device
The system is coming up.  Please wait.
starting rpc services: rpcbind done.
Setting netmask of hme0 to 255.255.255.0
Setting default IPv4 interface for multicast: add net 224.0/4: gateway pegasus
Starting sshd...
This platform does not support both privilege separation and compression
Compression disabled
syslog service starting.
savecore: no dump device configured
savecore: no dump device configured
dumpadm: no swap devices could be configured as the dump device
Oct 28 14:06:20 pegasus savecore: no dump device configured
Print services started.
/dev/bd.off: not a serial device.
volume management starting.

  No VVR license installed on the system; vradmind not started.

  No VVR license installed on the system; in.vxrsyncd not started.
The system is ready.

pegasus console login:

Check extent of failures

Once the reboot is complete, the administrator then logs into the system and checks the status of the system. Note that the device c0t0d0s2 is listed as "failed", and the all plexes on that device are listed as "DISABLED/NODEVICE".

pegasus console login: root
Password: 
Last login: Mon Oct 28 12:27:20 on console
Oct 28 14:06:52 pegasus login: ROOT LOGIN /dev/console
Sun Microsystems Inc.   SunOS 5.8       Generic February 2000
You have new mail.

# vxdisk list
DEVICE       TYPE      DISK         GROUP        STATUS
c0t1d0s2     sliced    rootmirror   rootdg       online
-            -         rootdisk     rootdg       failed was:c0t0d0s2

# vxprint -ht
Disk group: rootdg

DG NAME         NCONFIG      NLOG     MINORS   GROUP-ID
DM NAME         DEVICE       TYPE     PRIVLEN  PUBLEN   STATE
RV NAME         RLINK_CNT    KSTATE   STATE    PRIMARY  DATAVOLS  SRL
RL NAME         RVG          KSTATE   STATE    REM_HOST REM_DG    REM_RLNK
V  NAME         RVG          KSTATE   STATE    LENGTH   READPOL   PREFPLEX UTYPE
PL NAME         VOLUME       KSTATE   STATE    LENGTH   LAYOUT    NCOL/WID MODE
SD NAME         PLEX         DISK     DISKOFFS LENGTH   [COL/]OFF DEVICE   MODE
SV NAME         PLEX         VOLNAME  NVOLLAYR LENGTH   [COL/]OFF AM/NM    MODE
DC NAME         PARENTVOL    LOGVOL
SP NAME         SNAPVOL      DCO

dg rootdg       default      default  0        1035555399.1025.pegasus

dm rootdisk     -            -        -        -        NODEVICE
dm rootmirror   c0t1d0s2     sliced   3359     17690400 -

v  rootvol      -            ENABLED  ACTIVE   13423200 ROUND     -        root
pl rootvol-01   rootvol      DISABLED NODEVICE 13423200 CONCAT    -        RW
sd rootdisk-B0  rootvol-01   rootdisk 17690399 1        0         -        NDEV
sd rootdisk-02  rootvol-01   rootdisk 0        13423199 1         -        NDEV
pl rootvol-02   rootvol      ENABLED  ACTIVE   13423200 CONCAT    -        RW
sd rootmirror-01 rootvol-02  rootmirror 0      13423200 0         c0t1d0   ENA

v  swapvol      -            ENABLED  ACTIVE   2100000  ROUND     -        swap
pl swapvol-01   swapvol      DISABLED NODEVICE 2100000  CONCAT    -        WO
sd rootdisk-01  swapvol-01   rootdisk 13423199 2100000  0         -        NDEV
pl swapvol-02   swapvol      ENABLED  ACTIVE   2100000  CONCAT    -        RW
sd rootmirror-02 swapvol-02  rootmirror 13423200 2100000 0        c0t1d0   ENA

v  var          -            ENABLED  ACTIVE   2100000  ROUND     -        fsgen
pl var-01       var          DISABLED NODEVICE 2100000  CONCAT    -        WO
sd rootdisk-03  var-01       rootdisk 15523199 2100000  0         -        NDEV
pl var-02       var          ENABLED  ACTIVE   2100000  CONCAT    -        RW
sd rootmirror-03 var-02      rootmirror 15523200 2100000 0        c0t1d0   ENA

Replace failed disk and restore redundancy

The administrator replaces the failed disk with a new disk of the same geometry. Depending on the system model, the disk replacement may require that the system be powered down. Once the operating system can "see" the new disk c0t0d0 via the format command, the administrator tells Veritas volume manager to rescan the system via the "vxdctl enable" command.

# format
Searching for disks...done


AVAILABLE DISK SELECTIONS:
       0. c0t0d0 <SEAGATE-ST19171W-0024 cyl 5266 alt 2 hd 20 sec 168>
          /pci@1f,4000/scsi@3/sd@0,0
       1. c0t1d0 <SEAGATE-ST19171W-0024 cyl 5266 alt 2 hd 20 sec 168>
          /pci@1f,4000/scsi@3/sd@1,0
Specify disk (enter its number): ^D

# vxdctl enable

# vxdisk list
DEVICE       TYPE      DISK         GROUP        STATUS
c0t0d0s2     sliced    -            -            error
c0t1d0s2     sliced    rootmirror   rootdg       online
-            -         rootdisk     rootdg       failed was:c0t0d0s2

Now the administrator can make use of "vxdiskadm" to manage the process of replacing the boot disk volumes.

# vxdiskadm

Volume Manager Support Operations
Menu: VolumeManager/Disk

 1      Add or initialize one or more disks
 2      Encapsulate one or more disks
 3      Remove a disk
 4      Remove a disk for replacement
 5      Replace a failed or removed disk
 6      Mirror volumes on a disk
 7      Move volumes from a disk
 8      Enable access to (import) a disk group
 9      Remove access to (deport) a disk group
 10     Enable (online) a disk device
 11     Disable (offline) a disk device
 12     Mark a disk as a spare for a disk group
 13     Turn off the spare flag on a disk
 14     Unrelocate subdisks back to a disk
 15     Exclude a disk from hot-relocation use
 16     Make a disk available for hot-relocation use
 17     Prevent multipathing/Suppress devices from VxVM's view
 18     Allow multipathing/Unsuppress devices from VxVM's view
 19     List currently suppressed/non-multipathed devices
 20     Change the disk naming scheme
 21     Get the newly connected/zoned disks in VxVM view
 list   List disk information


 ?      Display help about menu
 ??     Display help about the menuing system
 q      Exit from menus

Select an operation to perform: 4


Remove a disk for replacement
Menu: VolumeManager/Disk/RemoveForReplace

  Use this menu operation to remove a physical disk from a disk
  group, while retaining the disk name.  This changes the state
  for the disk name to a "removed" disk.  If there are any
  initialized disks that are not part of a disk group, you will be
  given the option of using one of these disks as a replacement.

Enter disk name [<disk>,list,q,?] list

Disk group: rootdg

DM NAME         DEVICE       TYPE     PRIVLEN  PUBLEN   STATE

dm rootdisk     -            -        -        -        NODEVICE
dm rootmirror   c0t1d0s2     sliced   3359     17690400 -

Enter disk name [<disk>,list,q,?] rootdisk

  The following volumes will lose mirrors as a result of this
  operation:

        rootvol swapvol var

  No data on these volumes will be lost.

  The requested operation is to remove disk rootdisk from disk group
  rootdg.  The disk name will be kept, along with any volumes using
  the disk, allowing replacement of the disk.

  Select "Replace a failed or removed disk" from the main menu
  when you wish to replace the disk.

Continue with operation? [y,n,q,?] (default: y) y

  Removal of disk rootdisk completed successfully.

Remove another disk? [y,n,q,?] (default: n) n

Volume Manager Support Operations
Menu: VolumeManager/Disk

 1      Add or initialize one or more disks
 2      Encapsulate one or more disks
 3      Remove a disk
 4      Remove a disk for replacement
 5      Replace a failed or removed disk
 6      Mirror volumes on a disk
 7      Move volumes from a disk
 8      Enable access to (import) a disk group
 9      Remove access to (deport) a disk group
 10     Enable (online) a disk device
 11     Disable (offline) a disk device
 12     Mark a disk as a spare for a disk group
 13     Turn off the spare flag on a disk
 14     Unrelocate subdisks back to a disk
 15     Exclude a disk from hot-relocation use
 16     Make a disk available for hot-relocation use
 17     Prevent multipathing/Suppress devices from VxVM's view
 18     Allow multipathing/Unsuppress devices from VxVM's view
 19     List currently suppressed/non-multipathed devices
 20     Change the disk naming scheme
 21     Get the newly connected/zoned disks in VxVM view
 list   List disk information


 ?      Display help about menu
 ??     Display help about the menuing system
 q      Exit from menus

Select an operation to perform: 5


Replace a failed or removed disk
Menu: VolumeManager/Disk/ReplaceDisk

  Use this menu operation to specify a replacement disk for a disk
  that you removed with the "Remove a disk for replacement" menu
  operation, or that failed during use.  You will be prompted for
  a disk name to replace and a disk device to use as a replacement.
  You can choose an uninitialized disk, in which case the disk will
  be initialized, or you can choose a disk that you have already
  initialized using the Add or initialize a disk menu operation.

Select a removed or failed disk [<disk>,list,q,?] list

Disk group: rootdg

DM NAME         DEVICE       TYPE     PRIVLEN  PUBLEN   STATE

dm rootdisk     -            -        -        -        REMOVED


Select a removed or failed disk [<disk>,list,q,?] rootdisk

Select disk device to initialize [<address>,list,q,?] list

DEVICE       DISK         GROUP        STATUS
c0t0d0       -            -            error
c0t1d0       rootmirror   rootdg       online

Select disk device to initialize [<address>,list,q,?] c0t0d0

  The following disk device has a valid VTOC, but does not appear to have
  been initialized for the Volume Manager.  If there is data on the disk
  that should NOT be destroyed you should encapsulate the existing disk
  partitions as volumes instead of adding the disk as a new disk.
  Output format: [Device_Name]

  c0t0d0

Encapsulate this device? [y,n,q,?] (default: y) n

  c0t0d0

Instead of encapsulating, initialize? [y,n,q,?] (default: n) y

  The requested operation is to initialize disk device c0t0d0 and
  to then use that device to replace the removed or failed disk
  rootdisk in disk group rootdg.

Continue with operation? [y,n,q,?] (default: y) 

  Replacement of disk rootdisk in group rootdg with disk device
  c0t0d0 completed successfully.

Replace another disk? [y,n,q,?] (default: n) n

Volume Manager Support Operations
Menu: VolumeManager/Disk

 1      Add or initialize one or more disks
 2      Encapsulate one or more disks
 3      Remove a disk
 4      Remove a disk for replacement
 5      Replace a failed or removed disk
 6      Mirror volumes on a disk
 7      Move volumes from a disk
 8      Enable access to (import) a disk group
 9      Remove access to (deport) a disk group
 10     Enable (online) a disk device
 11     Disable (offline) a disk device
 12     Mark a disk as a spare for a disk group
 13     Turn off the spare flag on a disk
 14     Unrelocate subdisks back to a disk
 15     Exclude a disk from hot-relocation use
 16     Make a disk available for hot-relocation use
 17     Prevent multipathing/Suppress devices from VxVM's view
 18     Allow multipathing/Unsuppress devices from VxVM's view
 19     List currently suppressed/non-multipathed devices
 20     Change the disk naming scheme
 21     Get the newly connected/zoned disks in VxVM view
 list   List disk information


 ?      Display help about menu
 ??     Display help about the menuing system
 q      Exit from menus

Select an operation to perform: q

Goodbye.

Having replaced the disk in Veritas volume manager, the disk device is now listed as "online", and VxVM is in the process of attaching the replacement plexes to the original volumes.

# vxdisk list
DEVICE       TYPE      DISK         GROUP        STATUS
c0t0d0s2     sliced    rootdisk     rootdg       online
c0t1d0s2     sliced    rootmirror   rootdg       online

# vxprint -ht
Disk group: rootdg

DG NAME         NCONFIG      NLOG     MINORS   GROUP-ID
DM NAME         DEVICE       TYPE     PRIVLEN  PUBLEN   STATE
RV NAME         RLINK_CNT    KSTATE   STATE    PRIMARY  DATAVOLS  SRL
RL NAME         RVG          KSTATE   STATE    REM_HOST REM_DG    REM_RLNK
V  NAME         RVG          KSTATE   STATE    LENGTH   READPOL   PREFPLEX UTYPE
PL NAME         VOLUME       KSTATE   STATE    LENGTH   LAYOUT    NCOL/WID MODE
SD NAME         PLEX         DISK     DISKOFFS LENGTH   [COL/]OFF DEVICE   MODE
SV NAME         PLEX         VOLNAME  NVOLLAYR LENGTH   [COL/]OFF AM/NM    MODE
DC NAME         PARENTVOL    LOGVOL
SP NAME         SNAPVOL      DCO

dg rootdg       default      default  0        1035555399.1025.pegasus

dm rootdisk     c0t0d0s2     sliced   3359     17690400 -
dm rootmirror   c0t1d0s2     sliced   3359     17690400 -

v  rootvol      -            ENABLED  ACTIVE   13423200 ROUND     -        root
pl rootvol-01   rootvol      ENABLED  STALE    13423200 CONCAT    -        WO
sd rootdisk-05  rootvol-01   rootdisk 2100000  13423200 0         c0t0d0   ENA
pl rootvol-02   rootvol      ENABLED  ACTIVE   13423200 CONCAT    -        RW
sd rootmirror-01 rootvol-02  rootmirror 0      13423200 0         c0t1d0   ENA

v  swapvol      -            ENABLED  ACTIVE   2100000  ROUND     -        swap
pl swapvol-01   swapvol      DISABLED RECOVER  2100000  CONCAT    -        WO
sd rootdisk-06  swapvol-01   rootdisk 15523200 2100000  0         c0t0d0   ENA
pl swapvol-02   swapvol      ENABLED  ACTIVE   2100000  CONCAT    -        RW
sd rootmirror-02 swapvol-02  rootmirror 13423200 2100000 0        c0t1d0   ENA

v  var          -            ENABLED  ACTIVE   2100000  ROUND     -        fsgen
pl var-01       var          DISABLED RECOVER  2100000  CONCAT    -        WO
sd rootdisk-04  var-01       rootdisk 0        2100000  0         c0t0d0   ENA
pl var-02       var          ENABLED  ACTIVE   2100000  CONCAT    -        RW
sd rootmirror-03 var-02      rootmirror 15523200 2100000 0        c0t1d0   ENA

# vxtask list
TASKID  PTID TYPE/STATE    PCT   PROGRESS
   161           PARENT/R  0.00% 3/0(1) VXRECOVER rootdisk
   162   162     ATCOPY/R 01.22% 0/13423200/163680 PLXATT rootvol rootvol-01

After about an hour, all of the plexes have been synchronized, and full operating system redundancy has been restored:

# vxtask list
TASKID  PTID TYPE/STATE    PCT   PROGRESS

# vxprint -ht
Disk group: rootdg

DG NAME         NCONFIG      NLOG     MINORS   GROUP-ID
DM NAME         DEVICE       TYPE     PRIVLEN  PUBLEN   STATE
RV NAME         RLINK_CNT    KSTATE   STATE    PRIMARY  DATAVOLS  SRL
RL NAME         RVG          KSTATE   STATE    REM_HOST REM_DG    REM_RLNK
V  NAME         RVG          KSTATE   STATE    LENGTH   READPOL   PREFPLEX UTYPE
PL NAME         VOLUME       KSTATE   STATE    LENGTH   LAYOUT    NCOL/WID MODE
SD NAME         PLEX         DISK     DISKOFFS LENGTH   [COL/]OFF DEVICE   MODE
SV NAME         PLEX         VOLNAME  NVOLLAYR LENGTH   [COL/]OFF AM/NM    MODE
DC NAME         PARENTVOL    LOGVOL
SP NAME         SNAPVOL      DCO

dg rootdg       default      default  0        1035555399.1025.pegasus

dm rootdisk     c0t0d0s2     sliced   3359     17690400 -
dm rootmirror   c0t1d0s2     sliced   3359     17690400 -

v  rootvol      -            ENABLED  ACTIVE   13423200 ROUND     -        root
pl rootvol-01   rootvol      ENABLED  ACTIVE   13423200 CONCAT    -        RW
sd rootdisk-05  rootvol-01   rootdisk 2100000  13423200 0         c0t0d0   ENA
pl rootvol-02   rootvol      ENABLED  ACTIVE   13423200 CONCAT    -        RW
sd rootmirror-01 rootvol-02  rootmirror 0      13423200 0         c0t1d0   ENA

v  swapvol      -            ENABLED  ACTIVE   2100000  ROUND     -        swap
pl swapvol-01   swapvol      ENABLED  ACTIVE   2100000  CONCAT    -        RW
sd rootdisk-06  swapvol-01   rootdisk 15523200 2100000  0         c0t0d0   ENA
pl swapvol-02   swapvol      ENABLED  ACTIVE   2100000  CONCAT    -        RW
sd rootmirror-02 swapvol-02  rootmirror 13423200 2100000 0        c0t1d0   ENA

v  var          -            ENABLED  ACTIVE   2100000  ROUND     -        fsgen
pl var-01       var          ENABLED  ACTIVE   2100000  CONCAT    -        RW
sd rootdisk-04  var-01       rootdisk 0        2100000  0         c0t0d0   ENA
pl var-02       var          ENABLED  ACTIVE   2100000  CONCAT    -        RW
sd rootmirror-03 var-02      rootmirror 15523200 2100000 0        c0t1d0   ENA