Spectrum DDM Database Save Fails with error - setting server variable "old alter table" back to 0"

Products

• Spectrum
• Network Observability

Issue/Introduction

When using ddm_save.pl to save the DDM database, it fails.  You can see a similar stacktrace in the log:

190506 16:18:30 MAIN    INFO: An exceptional situation is detected therefore printing 
 stacktrace. mysqlbackup might able to recover from this situation.

stack_bottom = 0 thread_stack 0x10000
/opt/CA/Spectrum/SS/DDM/mysqlbackup(my_print_stacktrace+0x2e)[0x6c134e]
/opt/CA/Spectrum/SS/DDM/mysqlbackup(_ZN3meb9ExceptionC1ENS_14enum_exit_codeEPKcS3_i+0xf1)[0x49da21]
/opt/CA/Spectrum/SS/DDM/mysqlbackup(_ZN3meb17Exception_factory16create_exceptionENS_14enum_exit_codeEPKcS3_i+0x48)[0x4a46a8]
/opt/CA/Spectrum/SS/DDM/mysqlbackup(_ZN3meb11Meb_session7performEv+0xe4)[0x4a4104]
/opt/CA/Spectrum/SS/DDM/mysqlbackup(_ZN3meb20mysqlbackup_parallelEiPPc+0x2a)[0x49d67a]
/opt/CA/Spectrum/SS/DDM/mysqlbackup(main+0x64)[0x49d814]
/lib64/libc.so.6(__libc_start_main+0xf5)[0x7f023af47c05]
/opt/CA/Spectrum/SS/DDM/mysqlbackup[0x49d529]
190506 16:18:30 MAIN TRACE_1: created exception, file: '/export/home/pb2/build/sb_0-29729096-1532351551.24/meb-4.1.2/src/meb/meb_session.cpp'  line: 635  num: 2  msg: 'NULL'
mysqlbackup failed with errors!
190506 16:18:30 MAIN TRACE_2: [CLOSE] 8:/opt/CA/Spectrum/mysql/data/ib_logfile0
190506 16:18:30 MAIN TRACE_2: [CLOSE] 9:/opt/CA/Spectrum/mysql/data/ib_logfile0
190506 16:18:30 MAIN TRACE_2: [CLOSE] 10:/opt/CA/Spectrum/SS-DB-Backup/db_20190506_1549.DDMDb.tmpdir/datadir/ibbackup_logfile
190506 16:18:30 MAIN    INFO: Setting server system variable 'old_alter_table' back to '0'.
190506 16:18:30 MAIN TRACE_1: Executing MySQL query 'SET @@GLOBAL.old_alter_table = 0'

Environment

Spectrum Release: 10.4, 20.2

Cause

The mysql database is still running as type myisam.  It needs to be converted to innodb to work with the perl script (ddm_save.pl).

Resolution

Manually run the convert script to convert mysql from myisam to innodb using the "convert_current_myisam_to_innodb.pl" script:

TechDocs :DX NetOps Spectrum 23.3 : Post Migration Tasks