Restoring with Sysback on AIX 4.1 with SSA disks


OS Level: AIX Version 4.1.5, Sysback Version, 3590
Type/Model: SP High Node (9076)


While attempting to recreate the rootvg in a Sysback restore, an error is received.

After booting off of a Sysback full system backup tape, getting into the Sysback Installation Main Menu and starting the install from tape for cloning to a system with SSA disks, the following errors are received:

Making volume group...                                                  
/usr/sbin/extendvg [205]: 464 6 killed                                  
0516-792 extendvg: Unable to extend volume group                        
0516-792 mkvg: Unable to extend volume group                            
Error creating volume group rootvg using defaults                       
0516-696 mkvg: hdisk0 belongs to another volume group                   
0516-862 mkvg: hdisk0 belongs to another volume group                   
Start maintenance shell --> y                                           
ksh> mkvg -fy rootvg -s 8 hdisk0 hdisk1                                 
mkvg [285]: 4976 killed                                                 
0516-862 mkvg: Unable to create volume group                            
./mkvg[40]: cannot fork: no swap space                                  


The problem is caused by a defect with AIX 4.1 and how it manages memory requirements for the SSA adapter device driver. No matter how much memory is available to the RAMdisk, AIX 4.1 will not reserve enough memory for the SSA adapter. There are two ways to work around this situation: either physically remove the SSA adapters, or create a new boot image that does not include any SSA proto files. The particular case involving this problem in this document describes a previously unencountered problem with performing the restore with Sysback even after the SSA adapters had been physically removed from the affected system.

The process fails when the getlvodm command is run within a system maintenance shell. However, executing the command from the command line allows the process to run.

It has not been determined why the getlvodm command does not run from a script. There may be a possible defect with one of the following filesets:, bos.rte.lvm, and bos.rte.filesystems. The level of these filesets should be checked.

The AIX 4.1/SSA problem will affect installations from both Sysback and mksysb. The problem occurs during any tape installs, not just when cloning.

Complete the following steps.

  1. Remove the SSA adapters from the system being cloned.
  2. Boot the system off of the Sysback tape
  3. Add each disk into the volume group with the following commands:
    1. Get the vgid of rootvg. Enter:
         getlvodm -v rootvg 
    2. Get the pvid of all the disks. Enter:
         getlvodm -P 
    3. Run the following commands for each disk:
         linstallpv -N [hdisk#] -g vgid -f 
         putlvodm -p vgid pvid
  4. Exit
  5. The restore should now start and the mklv and mkjfs commands should run.

[ Doc Ref: 94466983917294     Publish Date: Dec. 23, 1999     4FAX Ref: none ]