Starting Shadow Database on UNIX

At system startup, both the live and Shadow Database partitions must be disabled. The clean log partition must be enabled at boot time.

A Shadow startup script controls the enabling of the appropriate partition before the Reality central daemon is started.

The Shadow partition remains disabled at all times during normal database operation. The only exceptions are the nightly update and FILE-SAVE procedure, the swapping of the live/Shadow pair and the re-making of the Shadow Database to be the live one during the database recovery procedure.

Shadow Startup Script

The Shadow startup script runs at boot-time to check if each live database in /usr/realman/shadow has been closed down cleanly. If so, it enables and starts up the live database. If not, it enables and starts up the associated Shadow Database instead.

Startup Procedure After Clean Shutdown

If the live database was shutdown cleanly, then the following message is displayed:

Live partition for shadow pair pair_name mounted.

or

Unable to mount live partition for shadow pair pair_name

Startup Procedure After Dirty Shutdown

If the live database was not shutdown cleanly, then the following message is displayed:

Live database <dbase_name> is dirty.
Mounting the shadow partition 

One of the following messages will then be displayed:

Shadow partition for shadow pair pair_name mounted.
After system re-boot is complete, run tlmenu failure and recovery
options 1, 2 and 3 on database shadow_database

or

Unable to mount shadow partition for shadow pair pair_name

Use of File System Default Tables to Mount/Unmount Partitions

Partitions to be mounted at boot time are defined in the file system default table. This is held in the file:

• /etc/vfstab on Solaris.
• /etc/filesystems on AIX.
• /etc/fstab on Linux.

The file system default table defines all partitions (mounted or not mounted) and specifies whether they are to be mounted. Hence, it provides all partition information required by the Shadow startup script and tlmenu to mount and unmount database partitions.

The table must contain a list of all partitions to be mounted or not mounted at boot time. Field 6 of the table indicates whether a partition is to be mounted or not mounted. yes  indicates 'mounted'; no  indicates 'not mounted'.

The following gives an example of entries in the file system default table:

/dev/dsk/m197_c0d0s9 /dev/rdsk/m197_c0d0s9 /cleanlog	ufs 1 yes -
/dev/dsk/m197_c0d0sa /dev/rdsk/m197_c0d0sa /real1	ufs 1 no  -
/dev/dsk/m197_c0d0sb /dev/rdsk/m197_c0d0sb /real2	ufs 1 no  -

This provides all the mount information required by tlmenu.

Refer to the appropriate man page or the UNIX System Files and Device Reference Manual for a description of the fields in the file system default table.