Cifs troubleshooting (NetApp)

Cifs troubleshooting:

Cifs client access

The flow of communications from cifs client to a storage appliance in a multiprotocol environment.

1.       PC request access to the data.

2.       Storage appliance check with DC for the authentication.

3..   DC reply: authentication or guest.

4.       If guest access is denied unless cifs. guest-account is set.

5.       Storage appliance maps the NT account to unix username.

6.       Storage appliance compares NT account info with share ACL.

7.       Storage appliance compare NT account info with file ACL or UNIX username with file permissions.

8.       If users have access to the share and the file, the storage appliance grants the access.

Phase 1: PC request access to the data.

Potential issue

1.       Network failed or slow.

2.       Client not authenticated to DC.

3.       Client not able to find the storage appliance.

The below are the cmd by which you can figure it out.

Filer>ifstat

Filer>netdiag

Filer> ping the DNS or by username.

Client>tracert

Filer>nbtstat(if using WINS(windows internet name services)).

Phase 2: Storage appliance check with DC for the authentication.

Potential issue:

Domain controller communicates and trust across multiple domains can fail.

Cmd:

Filer> cifs testdc

Filer>options cifs.trace_login  is set to on.(note: to prevent the deluge of the console and log messages , Netapp recommend the toggling this options off after the troubleshooting is complete.)

Phase 3: DC reply:  authentication or guest

Potential issue:

Authenticated result is not what was expected, Need to check the details of mapping.

Cmd:

      Filer> wcc  -s  username

     Filer>  options cifs.trace_login on

Phase 4:if guest account is denied unless

Potential issue

Guest access is denied

Cmd:

Filer>options cifs .guest_account

Phase 5:stoeage appliance maps NT account to unix username

Potential issue:

Account does not map, or UNIX username does not exit.

Cmd:

Check /etc/psswd file

Check /etc/usermap.cfg file

nis info (if using nis)

filer>options nis.group_update_schedule

Phase6: Storage appliance compare NT account info with share ACL.

Potential issue:

User does not have access to the share.

Cmd:

Filer> cifs shares

Client>computer management(wind 2000)

Phase7: storage appliance compare NT account info with file ACL, or unix username with file permission.

Potential issue:

User does not have access to file.

Cmd:

Filer> qtree status( check security style)

Win clent> Explorer

Unix client >ls –l