Symptoms

a. NetBackup bptm/bpdm logs show the following error for the failing replication job. 14:23:57.272 [22873] 242110:bptm:22873:nbu.xxx.xx: [5959:B4CBD0] ddcl_nfs_PLU_get_lsu_replication(): rpc failed with nsource 0, ntarget 1 14:23:57.272 [22873] 242110:bptm:22873:nbu.xxx.xx: /usr/openv/lib/ost-plugins/libstspiDataDomain.so:stspi_get_lsu_replication_prop_v11 STS_EPLUGIN RPC error [DDErrNo = 5040 (calling system(), returns nonzero)] 14:23:57.272 [22873] ost_proxy_replicate: rpl_build_target_svr_list() returned, retval=2060046 b. The DDboost precert logs show the following errors. 33309:[31571] [140111117678464] [410] Fri Jun 16 17:12:10.401 2023 ERROR: [7B53:12A2BD0] ddcl_nfs_ost_get_lsu_replication(): rpc failed with nsource 0, ntarget 1 c. The following errors are observed in the DDFS logs [root@data-domain-dev-vm c170252671]# grep -rni "nfsproc3_ostgetlsureplication_3_svc_helper" bundle_dd1_2023-06-16_17-20-30/ddr/var/log/debug/ddfs.info 36493:06/16 13:53:56.797604 [7ff5a9c2b500] ERROR: nfsproc3_ostgetlsureplication_3_svc_helper: nsource==0 but a replicate-from association found 45933:06/16 14:23:57.219289 [7ff5a9c15cc0] ERROR: nfsproc3_ostgetlsureplication_3_svc_helper: nsource==0 but a replicate-from association found

Cause

The same storage unit is used as both the source and destination in the AIR topology (Cascading AIR configuration).Example:DDBoost storage unit (dd2SU) association on the "Source" DD system - dd2 dd2: DDBOOST Association Show ------------------------ Local Storage Unit Direction Remote Host Remote Storage Unit Import To ------------------ -------------- ----------- ------------------- --------- dd2SU replicate-from dd1 dd1SU - dd2SU replicate-to dd3 dd3SU - ------------------ -------------- ----------- ------------------- --------- DDBoost storage unit association on the "Destination" DD system - dd3 dd3: DDBOOST Association Show ------------------------ Local Storage Unit Direction Remote Host Remote Storage Unit Import To ------------------ -------------- ----------- ------------------- --------- dd3SU replicate-from dd2 dd2SU - ------------------ -------------- ----------- ------------------- --------- Looking at the DDBoost storage unit association on the "source" DD system, it is noted that storage unit - dd2SU is configured as Source (replicate-to relationship) and Destination (replicate-from relationship) for different DD systems.The DDBoost association CLI allows this configuration on the DD system.As part of the replication workflow, NetBackup tries to read the destination storage units for the source storage unit - dd2SU. Based on the current implementation of the OST plug-in and DDBoost client, It reads the association database in the system and encounters the unexpected association which treats storage unit - dd2SU as a destination (replicate-from relationship)Because of this configuration, the DD server returns the error which causes failure for the replication jobs.We should not have the same storage unit configured as source and destination in the AIR topology. Based on the registry database iteration, the replication job may fail as per the log message posted above.

Resolution

Possible solutions: Configure the DDBoost storage unit association such that separate storage units are used for different AIR topologies.The above DDboost association can be changed as below to resolve this issue. Create a new DDBoost storage unit. Example:New association dd2: DDBOOST Association Show ------------------------ Local Storage Unit Direction Remote Host Remote Storage Unit Import To ------------------ -------------- ----------- ------------------- --------- dd2SU replicate-from dd1 dd1SU - dd2SU_local replicate-to dd3 dd3SU - ------------------ -------------- ----------- ------------------- --------- dd3: DDBOOST Association Show ------------------------ Local Storage Unit Direction Remote Host Remote Storage Unit Import To ------------------ -------------- ----------- ------------------- --------- dd3SU replicate-from dd2 dd2SU_local - ------------------ -------------- ----------- ------------------- ---------

Support Cases