When creating a DMS table space, DB2 checks the presence and
physical properties of all the table space containers specified
in the CREATE TABLESPACE command. When the user incorrectly
attempts to use the same (shared) container with multiple nodes,
SQL0294N (The container is already in use) will be returned
since the same container will already have been allocated and
used by a different node. However, in certain timing sensitive
scenarios, for example when the CREATE TABLESPACE command is
issued simultaneously on multiple nodes, the instance may panic.
Example:
1. Set up host1 and host2 as a partitioned system. Your
db2nodes.cfg will look similar to:
0 host1 0
1 host1 1
2 host1 2
3 host2 0
4 host2 1
5 host2 2
2. Choose two nodes residing on different hosts, and run the
following CREATE TABLESPACE command on both nodes at
approximately the same time. The command is purposely specifying
a shared container, and the action should fail with SQL0294N.
However, if the timing is right, the instance will panic
instead:
$ db2 "create tablespace ts1 managed by database using (file
'/<directory_shared_by_all_hosts>/ts1' 1M)"
DB21034E The command was processed as an SQL statement because
it was not a
valid Command Line Processor command. During SQL processing it
returned:
SQL1224N The database manager is not able to accept new
requests, has
terminated all requests in progress, or has terminated the
specified request
because of an error or a forced interrupt. SQLSTATE=55032
A good eyecatcher is container mismatch errors followed by
"sqlbDMSAddContainerRequest - rc == SQLB_CONTAINER_IN_USE" in
db2diag.log, for example:
2013-02-08-04.22.00.246987-360 I1022004A4198 LEVEL: Severe
PID : 74262 TID : 24000 PROC : db2sysc
1
INSTANCE: db2inst1 NODE : 001 DB : SAMPLE
APPHDL : 0-31789 APPID: *N0.db2inst1.130209025546
AUTHID : DB2INST1
EDUID : 24000 EDUNAME: db2agntp (SAMPLE) 1
FUNCTION: DB2 UDB, buffer pool services,
sqlbContainerTagIsValid, probe:100
DATA #1 : String, 20 bytes
*pTag(CONTAINER_TAG)
DATA #2 : Hexdump, 512 bytes
<...snip...>
CALLSTCK: (Static functions may not be resolved correctly, as
they are resolved to the nearest symbol)
[0] pdLog
[1] pdLog@glue436
[2] sqlbContainerTagIsValid
[3] sqlbDMSAddContainerRequest
[4] sqlbDoDMSAddContainerRequests
[5] sqlbDMSAddContainersToNewPool
[6] sqlbDMSCreatePool
[7] sqlbSetupPool
[8] sqlbCreatePool
[9] sqldPoolCreate
2013-02-08-04.22.00.261564-360 I1026203A3137 LEVEL: Severe
PID : 74262 TID : 24000 PROC : db2sysc
1
INSTANCE: db2inst1 NODE : 001 DB : SAMPLE
APPHDL : 0-31789 APPID: *N0.db2inst1.130209025546
AUTHID : DB2INST1
EDUID : 24000 EDUNAME: db2agntp (SAMPLE) 1
FUNCTION: DB2 UDB, buffer pool services,
sqlbContainerTagIsValid, probe:200
DATA #1 : Codepath, 8 bytes
2:3:10:11:12:14:15:16
DATA #2 : String, 19 bytes
iTag(CONTAINER_TAG)
DATA #3 : Hexdump, 512 bytes
<...snip...>
2013-02-08-04.22.00.264301-360 I1029341A580 LEVEL: Severe
PID : 74262 TID : 24000 PROC : db2sysc
1
INSTANCE: db2inst1 NODE : 001 DB : SAMPLE
APPHDL : 0-31789 APPID: *N0.db2inst1.130209025546
AUTHID : DB2INST1
EDUID : 24000 EDUNAME: db2agntp (SAMPLE) 1
FUNCTION: DB2 UDB, Common Trace API, sqlbfix, probe:1657
DATA #1 : String, 56 bytes
sqlbDMSAddContainerRequest - rc == SQLB_CONTAINER_IN_USE
DATA #2 : Hexdump, 4 bytes
0x07000001157FA9B4 : 8002 0039
...9
2013-02-08-04.22.00.289508-360 E1029922A937 LEVEL:
Critical
PID : 74262 TID : 24000 PROC : db2sysc
1
INSTANCE: db2inst1 NODE : 001 DB : SAMPLE
APPHDL : 0-31789 APPID: *N0.db2inst1.130209025546
AUTHID : DB2INST1
EDUID : 24000 EDUNAME: db2agntp (SAMPLE) 1
FUNCTION: DB2 UDB, RAS/PD component, pdStartFODC, probe:10
MESSAGE : ADM14001C An unexpected and critical error has
occurred: "Panic". |
