Backups were failing with 84 & 87 error intermittently - Destination Storage is Pure Disk Pool

Issue has been sorted out., seems the issue was with the host name resolution error.,

PD media servers were unable to resolve the clustered PD nodes., we got the below error from PD agent logs in all the PD media servers.,

December 25 08:51:52 ERR [139912246351616]: 31: CRRouteLookupFirst: internal error: found no route for 01a37b7be5065d3a712195475a90e628!
December 25 08:51:52 ERR [139912246351616]: 31: CRDCRefMode: Lookup route failed!
December 25 08:52:46 WARNING [139912246351616]: -1: addDo: The fingerprint cache limit of 20971520 has been reached for this session. DO 0a1daf473a7d43ad484760f47b10c4d7 will not be cached.
December 25 08:52:49 ERR [139912246351616]: 4: _CR_GwInitSuppressible: pd_getaddrinfo failed for host  using port 10082: Name or service not known
December 25 08:52:49 ERR [139912246351616]: 84: Failed to load route at line 4 in /usr/openv/pdde/pdag/var/rt/200_.recommended: could not initialize gateway: unable to resolve hostname
December 25 08:52:49 ERR [139912246351616]: 84: Router initialization failed: Failed to load route at line 4 in /usr/openv/pdde/pdag/var/rt/200_.recommended: could not initialize gateway: unable to resolve hostname

After adding host entries of all the PD nodes in all the PD media servers  - resolution error gets fixed and the backups are running fine.,

We are further checking with DNS team regarding the naming server issue.,

Thanks