Virtual Database (VDB) Provision to HPUX Targets May Fail with ORA-01157: cannot identify/lock data file (KBA1199)
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Issue
Provisioning of Oracle virtual databases (VDBs) on HPUX may fail with ORA-01157.
Oracle recommends tuning HPUX kernel values to optimize the performance of the system. In their recommendations for a single instance, Oracle suggests:
nprocs = 4096 nflocks = nprocs
Failure to adjust target systems appropriately as more virtual databases are created will inevitably lead to failure given the presence of at least one undersized kernel value. Please note that this document was compiled specifically to draw attention to nflocks, as DBA's frequently remember to increase shared memory and more frequently neglect nflocks.
Troubleshooting
Example alert log entry where nflocks is undersized:
ORA-00283: recovery session canceled due to errors ORA-01110: data file 1030: '/mnt/provision/myVDB2/datafile/oradata/myVDB/blaa.dbf' ORA-01157: cannot identify/lock data file 1030 - see DBWR trace file ORA-01110: data file 1030:
The key symptom in this case is "ORA-01157: cannot identify/lock data file"
The datafile number will be variable.
The key diagnostic is the kernel nflocks tunable during provision at or before failure. To check kernel parameters on HPUX inclusive nflocks:
# kcusage Tunable Usage / Setting ============================================= filecache_max 5606596608 / 48936038400 maxdsiz 32239616 / 1073741824 maxdsiz_64bit 48398336 / 4294967296 maxfiles_lim 1997 / 63488 maxssiz 786432 / 134217728 maxssiz_64bit 1835008 / 1073741824 maxtsiz 9797632 / 100663296 maxtsiz_64bit 402653184 / 1073741824 maxuprc 878 / 3686 max_thread_proc 101 / 1200 msgmbs 0 / 8 msgmni 2 / 4096 msgtql 0 / 4096 nflocks 3128 / 4096 ninode 4778 / 862284 nkthread 2173 / 8416 nproc 1376 / 4200 npty 0 / 60 nstrpty 4 / 60 nstrtel 0 / 60 nswapdev 1 / 32 nswapfs 0 / 32 semmni 25 / 4096 semmns 4957 / 8192 shmmax 1073741824 / 1073741824 shmmni 92 / 4096 shmseg 28 / 512
Above we see 3128 file locks (nflocks). In this case provisioning an additional VDB failed as there was insufficient headroom based on the current nflocks setting.
Resolution
Configure nflocks and other HPUX kernel values appropriate to the workload required from the target system.
For example, in this instance doubling nflocks was sufficient:
# kctune nflocks=8196
External Links
Oracle Database Quick Installation Guide for HP-UX Itanium
Oracle 11g (11.2)
https://docs.oracle.com/cd/E11882_01/install.112/e24342/toc.htm
Oracle 12c