multiple logpartions: Initialization of log for 'restart' failed with 'LogSizeHasDecreased'

[Former Member]

We changed our maxdb (livecache)configuration configuration to use multiple logpartions via dbmstudio according this help:

http://help.sap.com/saphelp_nw73ehp1/helpdata/en/e5/f0a4d8c44641869551ea7b41926d9b/frameset.htm

old config: 2 logvolumes, with logpartition 1:

LogVolumeName001                 512000     F  /sapdb/LCD/saplog/DISKL001  1

LogVolumeName002                 512000     F  /sapdb/LCD/saplog/DISKL002  1

target config: 4 logvolumes with 4 logpartitions:

We added logvolume 3 and logvolume 4 (each 4 gb) in the dbmstudio dialogs and changed logvolume to partition 2 (field partition was editable)

After dbmstudio has  switched the db to offline and made logbackup, logvolume  2 was still belonging to logpartition 1:

> /sapdb/programs/bin/dbmcli -d LCD -u control,<passwort> param_getvolsall log
OK
UseMirroredLog                   NO
MaxLogVolumes                    8
LogVolumeName001                 512000     F  /sapdb/LCD/saplog/DISKL001  1
LogVolumeName002                 512000     F  /sapdb/LCD/saplog/DISKL002  1
LogVolumeName003                 512000     F  /sapdb/LCD/saplog/DISKL003  3
LogVolumeName004                 512000     F  /sapdb/LCD/saplog/DISKL004  4

So we tried the manual commands from  http://wiki.sdn.sap.com/wiki/display/MaxDB/HowTo+-+Usage+of+Multiple+Log+Partitions

dbmcli on LCD>param_put LogVolumePartition002 2
dbmcli on LCD>db_offline
dbmcli on LCD>db_admin
dbmcli on LCD>db_execute clear log   

When getting db online we got following error and the db was offline afterwards:

dbmcli on LCD>db_online
ERR
-24988,ERR_SQL: SQL error
-9407,System error: unexpected error
3,Database state: OFFLINE
Internal errorcode, Error code 6433 "system_error"
20028,Initialization of log for 'restart' failed with 'LogSizeHasDecreased'

but we haven't changed anything in logsize ?

We have found a temporary solution with deleting new logvolumes and reconfig logvolume 2 to logpartition 1 again: db could be activated again:

dbmcli on LCD>db_admin
dbmcli on LCD>param_delvolume 4 log
dbmcli on LCD>param_delvolume 3 log
dbmcli on LCD>param_put LogVolumePartition002 1
dbmcli on LCD>db_offline
dbmcli on LCD>db_admin  
 
dbmcli on LCD>param_getvalue LogVolumePartition001
OK
1
---
dbmcli on LCD>param_getvalue LogVolumePartition002
OK
1

dbmcli on LCD>db_execute clear log
dbmcli on LCD>db_online

dbmcli on LCD>param_getvolsall log
OK
UseMirroredLog                   NO
MaxLogVolumes                    8
LogVolumeName001                 512000     F  /sapdb/LCD/saplog/DISKL001  1
LogVolumeName002                 512000     F  /sapdb/LCD/saplog/DISKL002  1

I assume, that the reconfig from logvolume 2 has caused the problem. Maybe following would be a better solution  for the next try:

- delete logvolume 2

- add logvolumes 2,3 4 (in logpartition 2,3,4)

Any ideas  welcome....

[yashwanthkumar_kethineed]

Hi,

What is the value of parameter MaxLogWriterTasks

Post output of DBM command - param_directget MaxLogWriterTasks

Are you trying to move the LogVolume DISKL002 to Log Partition 2  ?

[Former Member]

MaxLogWriterTasks= 4

Yes, we tried to move the LogVolume DISKL002 to Log Partition 2  (see posting for details)

[yashwanthkumar_kethineed]

Run the steps in sequence:

db_execute clear log

// move Log Volume DISKL002 to partition 2

db_addvolume log "/sapdb/LCD/saplog/DISKL002" F 512000 partition 2

Check the configuration;

param_getvolsall log

db_admin

db_online