CIFS shares not accessible , when checked filer was busy and hung

[krishnavardhini]

Hi Team,

We are using ontap 7 mode, where first time we are receiving this kind of scenario where the requests of cifs was pending.

Could you please check and guide us with any possibilities to reduce the overhead of the requests on the filer.

Logs:

Thu May 4 09:00:00 BST [lhrcbx-fsxxh04:replication.dst.err:error]: SnapMirror: destination transfer from lhrbod-fsxxh03s:axbddtest to axbddtest : destination is not in snapmirrored state.
Thu May 4 09:00:03 BST [lhrcbx-fsxxh04:openssh.invalid.channel.req:warning]: SSH client (SSH-2.0-OpenSSH_7.4) from 161.2.11.167 sent unsupported channel request (10, env).
Thu May 4 09:03:58 BST [lhrcbx-fsxxh04:nbt.WINS.registrationTimeout:info]: NBT: No WINS server are responding. The filer will continue to try to register with WINS.
Thu May 4 09:08:10 BST [lhr-fsxxv04@lhrcbx-fsxxh04:cifs.stats.pBlkExhaust:info]: CIFS: All CIFS control blocks for the STANDARD pool are in use. The request for a new control block can not be granted.
Thu May 4 09:09:13 BST [lhr-fsxxv04@lhrcbx-fsxxh04:nbt.WINS.registrationTimeout:info]: NBT: No WINS server are responding. The filer will continue to try to register with WINS.
Thu May 4 09:14:30 BST [lhrcbx-fsxxh04:wafl.vol.autoSize.fail:info]: Unable to grow volume 'archive4a' to recover space: Volume cannot be grown beyond maximum growth limit
Thu May 4 09:21:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4b to lhrbod-fsxxh03:usergroup4b : request denied, previous request still processing.
Thu May 4 09:21:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4c to lhrbod-fsxxh03:usergroup4c : request denied, previous request still processing.
Thu May 4 09:21:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from v04root to lhrbod-fsxxh03:v04root : request denied, previous request still processing.
Thu May 4 09:22:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4b to lhrbod-fsxxh03:usergroup4b : request denied, previous request still processing.
Thu May 4 09:22:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4a to lhrbod-fsxxh03:usergroup4a : request denied, previous request still processing.
Thu May 4 09:22:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from v04root to lhrbod-fsxxh03:v04root : request denied, previous request still processing.
Thu May 4 09:22:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4d to lhrbod-fsxxh03:usergroup4d : request denied, previous request still processing.
Thu May 4 09:23:01 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4b to lhrbod-fsxxh03:usergroup4b : request denied, previous request still processing.
Thu May 4 09:23:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4a to lhrbod-fsxxh03:usergroup4a : request denied, previous request still processing.
Thu May 4 09:24:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from v04root to lhrbod-fsxxh03:v04root : request denied, previous request still processing.
Thu May 4 09:24:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from archive4a to lhrbod-fsxxh03:archive4a : request denied, previous request still processing.
Thu May 4 09:24:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4c to lhrbod-fsxxh03:usergroup4c : request denied, previous request still processing.
Thu May 4 09:24:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4a to lhrbod-fsxxh03:usergroup4a : request denied, previous request still processing.
Thu May 4 09:25:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from support to lhrbod-fsxxh03:support : request denied, previous request still processing.
Thu May 4 09:25:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4d to lhrbod-fsxxh03:usergroup4d : request denied, previous request still processing.
Thu May 4 09:25:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4c to lhrbod-fsxxh03:usergroup4c : request denied, previous request still processing.
Thu May 4 09:25:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4b to lhrbod-fsxxh03:usergroup4b : request denied, previous request still processing.
Thu May 4 09:26:01 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from axbh04 to lhrbod-fsxxh03:axbh04 : request denied, previous request still processing.
Thu May 4 09:26:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4c to lhrbod-fsxxh03:usergroup4c : request denied, previous request still processing.
Thu May 4 09:26:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4a to lhrbod-fsxxh03:usergroup4a : request denied, previous request still processing.
Thu May 4 09:26:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from v04root to lhrbod-fsxxh03:v04root : request denied, previous request still processing.
Thu May 4 09:27:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4c to lhrbod-fsxxh03:usergroup4c : request denied, previous request still processing.
Thu May 4 09:27:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4b to lhrbod-fsxxh03:usergroup4b : request denied, previous request still processing.
Thu May 4 09:27:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from axbh04 to lhrbod-fsxxh03:axbh04 : request denied, previous request still processing.
Thu May 4 09:27:26 BST [lhrcbx-fsxxh04: rlmauth_login_mgr:info]: mn505475 logged in from SP
Thu May 4 09:28:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from v04root to lhrbod-fsxxh03:v04root : request denied, previous request still processing.
Thu May 4 09:29:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4c to lhrbod-fsxxh03:usergroup4c : request denied, previous request still processing.
Thu May 4 09:29:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from v04root to lhrbod-fsxxh03:v04root : request denied, previous request still processing.
Thu May 4 09:29:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from archive4a to lhrbod-fsxxh03:archive4a : request denied, previous request still processing.
Thu May 4 09:30:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4a to lhrbod-fsxxh03:usergroup4a : request denied, previous request still processing.
Thu May 4 09:30:04 BST [lhrcbx-fsxxh04:openssh.invalid.channel.req:warning]: SSH client (SSH-2.0-OpenSSH_7.4) from 161.2.11.167 sent unsupported channel request (10, env).
Thu May 4 09:31:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from archive4a to lhrbod-fsxxh03:archive4a : request denied, previous request still processing.
Thu May 4 09:33:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from archive4a to lhrbod-fsxxh03:archive4a : request denied, previous request still processing.
Thu May 4 09:33:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4d to lhrbod-fsxxh03:usergroup4d : request denied, previous request still processing.
Thu May 4 09:33:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4c to lhrbod-fsxxh03:usergroup4c : request denied, previous request still processing.
Thu May 4 09:33:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4b to lhrbod-fsxxh03:usergroup4b : request denied, previous request still processing.
Thu May 4 09:34:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from archive4a to lhrbod-fsxxh03:archive4a : request denied, previous request still processing.
Thu May 4 09:34:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4a to lhrbod-fsxxh03:usergroup4a : request denied, previous request still processing.
Thu May 4 09:34:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from axbh04 to lhrbod-fsxxh03:axbh04 : request denied, previous request still processing.
Thu May 4 09:35:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4a to lhrbod-fsxxh03:usergroup4a : request denied, previous request still processing.
Thu May 4 09:35:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from axbh04 to lhrbod-fsxxh03:axbh04 : request denied, previous request still processing.
Thu May 4 09:36:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4d to lhrbod-fsxxh03:usergroup4d : request denied, previous request still processing.
Thu May 4 09:36:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4c to lhrbod-fsxxh03:usergroup4c : request denied, previous request still processing.
Thu May 4 09:36:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4b to lhrbod-fsxxh03:usergroup4b : request denied, previous request still processing.
Thu May 4 09:36:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from v04root to lhrbod-fsxxh03:v04root : request denied, previous request still processing.
Thu May 4 09:36:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from archive4a to lhrbod-fsxxh03:archive4a : request denied, previous request still processing.
Thu May 4 09:36:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from support to lhrbod-fsxxh03:support : request denied, previous request still processing.

#############

Wed May 3 06:07:58 BST [lhr-fsxxv04@lhrcbx-fsxxh04:cifs.stats.pBlkExhaust:info]: CIFS: All CIFS control blocks for the STANDARD pool are in use. The request for a new control block can not be granted.
Wed May 3 06:09:28 BST [lhrcbx-fsxxh04:wafl.vol.autoSize.fail:info]: Unable to grow volume 'archive4a' to recover space: Volume cannot be grown beyond maximum growth limit
Wed May 3 06:21:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from support to lhrbod-fsxxh03:support : request denied, previous request still processing.
Wed May 3 06:21:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4d to lhrbod-fsxxh03:usergroup4d : request denied, previous request still processing.
Wed May 3 06:21:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4c to lhrbod-fsxxh03:usergroup4c : request denied, previous request still processing.
Wed May 3 06:21:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4b to lhrbod-fsxxh03:usergroup4b : request denied, previous request still processing.
Wed May 3 06:21:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4a to lhrbod-fsxxh03:usergroup4a : request denied, previous request still processing.
Wed May 3 06:21:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from v04root to lhrbod-fsxxh03:v04root : request denied, previous request still processing.
Wed May 3 06:22:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from support to lhrbod-fsxxh03:support : request denied, previous request still processing.
Wed May 3 06:22:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4d to lhrbod-fsxxh03:usergroup4d : request denied, previous request still processing.
Wed May 3 06:22:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4c to lhrbod-fsxxh03:usergroup4c : request denied, previous request still processing.
Wed May 3 06:22:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4b to lhrbod-fsxxh03:usergroup4b : request denied, previous request still processing.
Wed May 3 06:22:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4a to lhrbod-fsxxh03:usergroup4a : request denied, previous request still processing.
Wed May 3 06:22:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from v04root to lhrbod-fsxxh03:v04root : request denied, previous request still processing.
Wed May 3 06:23:01 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4c to lhrbod-fsxxh03:usergroup4c : request denied, previous request still processing.
Wed May 3 06:23:01 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4b to lhrbod-fsxxh03:usergroup4b : request denied, previous request still processing.
Wed May 3 06:23:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4a to lhrbod-fsxxh03:usergroup4a : request denied, previous request still processing.
Wed May 3 06:23:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from v04root to lhrbod-fsxxh03:v04root : request denied, previous request still processing.
Wed May 3 06:23:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from support to lhrbod-fsxxh03:support : request denied, previous request still processing.
Wed May 3 06:23:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4d to lhrbod-fsxxh03:usergroup4d : request denied, previous request still processing.
Wed May 3 06:24:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4c to lhrbod-fsxxh03:usergroup4c : request denied, previous request still processing.
Wed May 3 06:24:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4b to lhrbod-fsxxh03:usergroup4b : request denied, previous request still processing.
Wed May 3 06:24:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4a to lhrbod-fsxxh03:usergroup4a : request denied, previous request still processing.
Wed May 3 06:24:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from v04root to lhrbod-fsxxh03:v04root : request denied, previous request still processing.
Wed May 3 06:24:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from archive4a to lhrbod-fsxxh03:archive4a : request denied, previous request still processing.
Wed May 3 06:24:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from support to lhrbod-fsxxh03:support : request denied, previous request still processing.
Wed May 3 06:25:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4c to lhrbod-fsxxh03:usergroup4c : request denied, previous request still processing.
Wed May 3 06:25:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4b to lhrbod-fsxxh03:usergroup4b : request denied, previous request still processing.
Wed May 3 06:25:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4a to lhrbod-fsxxh03:usergroup4a : request denied, previous request still processing.
Wed May 3 06:25:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from v04root to lhrbod-fsxxh03:v04root : request denied, previous request still processing.
Wed May 3 06:25:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from archive4a to lhrbod-fsxxh03:archive4a : request denied, previous request still processing.
Wed May 3 06:25:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from support to lhrbod-fsxxh03:support : request denied, previous request still processing.
Wed May 3 06:25:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4d to lhrbod-fsxxh03:usergroup4d : request denied, previous request still processing.
Wed May 3 06:26:01 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4c to lhrbod-fsxxh03:usergroup4c : request denied, previous request still processing.
Wed May 3 06:26:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4b to lhrbod-fsxxh03:usergroup4b : request denied, previous request still processing.
Wed May 3 06:26:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4a to lhrbod-fsxxh03:usergroup4a : request denied, previous request still processing.
Wed May 3 06:26:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from v04root to lhrbod-fsxxh03:v04root : request denied, previous request still processing.
Wed May 3 06:26:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from axbh04 to lhrbod-fsxxh03:axbh04 : request denied, previous request still processing.
Wed May 3 06:26:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from archive4a to lhrbod-fsxxh03:archive4a : request denied, previous request still processing.
Wed May 3 06:26:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from support to lhrbod-fsxxh03:support : request denied, previous request still processing.
Wed May 3 06:26:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4d to lhrbod-fsxxh03:usergroup4d : request denied, previous request still processing.
Wed May 3 06:27:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4a to lhrbod-fsxxh03:usergroup4a : request denied, previous request still processing.
Wed May 3 06:27:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from v04root to lhrbod-fsxxh03:v04root : request denied, previous request still processing.
Wed May 3 06:27:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from axbh04 to lhrbod-fsxxh03:axbh04 : request denied, previous request still processing.
Wed May 3 06:27:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from archive4a to lhrbod-fsxxh03:archive4a : request denied, previous request still processing.
Wed May 3 06:27:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from support to lhrbod-fsxxh03:support : request denied, previous request still processing.
Wed May 3 06:27:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4d to lhrbod-fsxxh03:usergroup4d : request denied, previous request still processing.
Wed May 3 06:27:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4c to lhrbod-fsxxh03:usergroup4c : request denied, previous request still processing.
Wed May 3 06:27:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4b to lhrbod-fsxxh03:usergroup4b : request denied, previous request still processing.
Wed May 3 06:28:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from v04root to lhrbod-fsxxh03:v04root : request denied, previous request still processing.
Wed May 3 06:28:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from axbh04 to lhrbod-fsxxh03:axbh04 : request denied, previous request still processing.
Wed May 3 06:28:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from archive4a to lhrbod-fsxxh03:archive4a : request denied, previous request still processing.
Wed May 3 06:28:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from support to lhrbod-fsxxh03:support : request denied, previous request still processing.
Wed May 3 06:28:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4d to lhrbod-fsxxh03:usergroup4d : request denied, previous request still processing.
Wed May 3 06:28:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4c to lhrbod-fsxxh03:usergroup4c : request denied, previous request still processing.
Wed May 3 06:28:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4b to lhrbod-fsxxh03:usergroup4b : request denied, previous request still processing.
Wed May 3 06:28:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4a to lhrbod-fsxxh03:usergroup4a : request denied, previous request still processing.
Wed May 3 06:29:01 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4d to lhrbod-fsxxh03:usergroup4d : request denied, previous request still processing.
Wed May 3 06:29:01 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4c to lhrbod-fsxxh03:usergroup4c : request denied, previous request still processing.
Wed May 3 06:29:01 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from usergroup4b to lhrbod-fsxxh03:usergroup4b : request denied, previous request still processing.
Wed May 3 06:29:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from v04root to lhrbod-fsxxh03:v04root : request denied, previous request still processing.
Wed May 3 06:29:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from axbh04 to lhrbod-fsxxh03:axbh04 : request denied, previous request still processing.
Wed May 3 06:29:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from archive4a to lhrbod-fsxxh03:archive4a : request denied, previous request still processing.
Wed May 3 06:29:02 BST [lhrcbx-fsxxh04:replication.src.err:error]: SnapMirror: source transfer from support to lhrbod-fsxxh03:support : request denied, previous request still processing.

[RossC]

Hi @krishnavardhini 

You may want to consider adjusting the schedule of the snapmirrors, as it looks like there is too many transfers requests happening at the same time. There are also other activities on controllers that eat into the CPU resources of the controller like the scheduled compression and deduplication activities, so you can change when they are scheduled as well to avoid everything all happening at once.

Consider reviewing this KB aticle for more information - https://kb.netapp.com/onprem/ontap/dp/SnapMirror/Top_10_SnapMirror_SnapVault_issues_and_solutions

[krishnavardhini]

Hi Ross,

Thank you for you reply.

We have the snapmirror scheduled every 15 minutes. We have this schedule for more than 10 years and we have not find any issues so far, but all of a sudden in recent times we are receiving below cifs.stats.pBlkExhaust  after which the filer get to hung and cifs sessions are slowly dropped.

Can you please guide us what remediation can be done for  "cifs.stats.pBlkExhaust" .

cifs.stats.pBlkExhaust

[Ontapforrum]

Following error is seen in your shared screenshot: "CIFS: All CIFS control blocks for the STANDARD pool are in use."

Please note: A "pBlk is the primary control block" that holds the context for each SMB request that passes through Data ONTAP 7-Mode. In theory, the length of time a pBlk will be in use is microseconds. There are situations where pBlks might be held up for longer periods of time. Once a Storage Controller reaches pBlk exhaustion, Data ONTAP will log one or all of the above warning messages and begin to reduce the TCP window of the currently connected CIFS clients to reduce the number of requests they can send. If all pBlks are consumed, it will block incoming CIFS requests from being processed until a pBlk becomes available.

There are many reasons for pBLK exhaustion, check the following KB to verify if there is another root cause.
https://kb.netapp.com/onprem/ontap/da/NAS/How_to_troubleshoot_pBlk_exhaustion

If no matches with the above KB described scenario, consider whether this caused by high Audit workload.
https://kb.netapp.com/Legacy/ONTAP/7Mode/pBLK_exhaustion_due_to_High_CIFS_audit_workloads

You may have been running the schedule for past 10 years, but is the filer (data growth & resources wise protocol/cpu/memory) same in the past 10 years ? Also,  If you have vFilers configured, the same pool of pBlks will be shared across all the vFilers to include vFiler0 (the physical controller itself). An additional and a separate pool of resources is not defined when you create a vFiler. Please take a look at the mentioned kbs and the steps suggested.