In order for a DB2 LOAD to be replicated from an HADR primary server to a standby server, DB2 must be able to access the load data on the standby. This is done using a shared file system and the COPY YES option on the LOAD command at the primary server.
If it is not possible to establish a shared file system, the standby server can be DEACTIVATED ("db2 deactivate database <db>") before the load runs and ACTIVATEd ("db2 activate database <db>") after the load has competed on the primary server and the load file has been manually copied to the standby (eg. via sftp or rcp). It is important to note that it is NOT the load input file that is copied to the standby, but a specially formatted file which DB2 creates as part of the load process.
Below is an example using the shared file system, which in this case is NFS.
In this document, commands on the primary server will be issued at db2inst1@linux and shown in blue text. Commands issued on the standby server will be issued at db2inst2@linux and shown in red text.
Step 1 – Setup Details
Test Setup:
Primary Server – db2hadr1
Primary Instance – db2inst1
Standby Server – db2hadr2
Standby Instance – db2inst2
NFS Details
db2inst1@linux:~> cat /etc/exports
/db2shared/ db2hadr2(rw,no_root_squash,sync)
db2inst2@linux:~> mount
<snip>
db2hadr1:/db2shared on /db2shared type nfs (rw,addr=192.168.217.151)
Step 2 – Create a test table that looks like the SAMPLE database EMPLOYEE table. We will call it “EMPCOPY.”
db2inst1@linux:~> db2 create table empcopy like employee
DB20000I The SQL command completed successfully.
Step 3 – Export some data from the EMPLOYEE table to load into our test table.
db2inst1@linux:~> db2 "export to /db2db/emp.del of del select * from employee"
SQL3104N The Export utility is beginning to export data to file
"/db2db/emp.del".
SQL3105N The Export utility has finished exporting "42" rows.
Number of rows exported: 42
Step 4 – LOAD the data utilizing the COPY YES option to copy the data to the shared file system.
db2inst1@linux:~> db2 "load from /db2db/emp.del of del replace into empcopy copy yes to /db2shared"
SQL3109N The utility is beginning to load data from file "/db2db/emp.del".
SQL3500W The utility is beginning the "LOAD" phase at time "01/08/2007
15:16:51.723262".
SQL3519W Begin Load Consistency Point. Input record count = "0".
SQL3520W Load Consistency Point was successful.
SQL3110N The utility has completed processing. "42" rows were read from the input file.
SQL3519W Begin Load Consistency Point. Input record count = "42".
SQL3520W Load Consistency Point was successful.
SQL3515W The utility has finished the "LOAD" phase at time
"01/08/2007 15:16:51.792947".
Number of rows read = 42
Number of rows skipped = 0
Number of rows loaded = 42
Number of rows rejected = 0
Number of rows deleted = 0
Number of rows committed = 42
Step 5 – Check to see if our LOAD data was copied to the standby server. Note that the timestamps from our load output and the copy file match and the tablespace ID (SAMPLE.x.db2inst1...) is for our tablespace.
Again, it is NOT the load input file that is copied to the standby, but a specially formatted file which DB2 creates as part of the load process.
db2inst2@linux:~> ls -l /db2shared/
total 2137
-rw-r----- 1 db2inst1 db2grp1 274456 2007-01-08 15:16 SAMPLE.4.db2inst1.NODE0000.CATN0000.20070108151651.001
Step 6 – Look for messages in the db2diag.log on the standby server to verify that the load was executed. The timestamps will match.
db2inst2@linux:~> less ~/sqllib/db2dump/db2diag.log
2007-01-08-15.26.38.393708-480 I862317G372 LEVEL: Warning
PID : 3500 TID : 366115520 PROC : db2agnti (SAMPLE) 0
INSTANCE: db2inst2 NODE : 000 DB : SAMPLE
APPHDL : 0-97
FUNCTION: DB2 UDB, database utilities, sqludcpy, probe:544
DATA #1 : String, 64 bytes
Starting to restore a load copy.
DB2INST1.EMPCOPY.20070108151651
<snip>
2007-01-08-15.26.48.774310-480 I863391G333 LEVEL: Warning
PID : 3500 TID : 366115520 PROC : db2agnti (SAMPLE) 0
INSTANCE: db2inst2 NODE : 000 DB : SAMPLE
APPHDL : 0-97
FUNCTION: DB2 UDB, database utilities, sqludcpy, probe:1134
MESSAGE : Load copy restore completed successfully.
Step 7 (Optional) – Just for fun, fail over, check the table and fail back.
db2inst2@linux:~> db2 takeover hadr on db sample
DB20000I The TAKEOVER HADR ON DATABASE command completed successfully.
db2inst2@linux:~> db2 connect to sample
Database Connection Information
Database server = DB2/LINUX 9.1.1
SQL authorization ID = DB2INST2
Local database alias = SAMPLE
db2inst2@linux:~> db2 "select count(*) from db2inst1.empcopy"
1
-----------
42
1 record(s) selected.
db2inst1@linux:/db2db> db2 takeover hadr on db sample
DB20000I The TAKEOVER HADR ON DATABASE command completed successfully.
Written By Craig Maddux
