Saturday, 28 May 2016

Maintaining NETBIOS Names in 7 to C Transitions

This is very simple!

Note 1: It’s not the place of this blog to question why one may want to keep NETBIOS names.
Note 2: Version of Clustered Data ONTAP is 8.3.2.

Scenario 1: Maintaining NETBIOS in a 1-1 Transition

We’re transitioning one 7-Mode pFiler/vFiler to one cDOT SVM. Post cutover of the 7-Mode filer, we want to maintain the old NETBIOS name. The 7-Mode system is called FAS101 and has a CIFS server called FAS101. The cDOT cluster is clu1, and an SVM exists called FAS101 and has a CIFS server called FAS101-NEW.

Post cutover; terminate CIFS on the 7-Mode FAS101.

FAS101> cifs terminate

Terminate CIFS on the cDOT SVM. Enter diag mode and modify the CIFS server’s NETBIOS name (requires domain administrative account.)

clu1::> cifs server modify -vserver FAS101 -status-admin down
clu1::> set d
clu1::*> cifs server modify -vserver FAS101 -cifs-server FAS101

In order to create an Active Directory machine account for the CIFS server, you must supply the name and password of a Windows account with sufficient privileges to add computers to the "CN=Computers" container within the "LAB.PRIV" domain.

Enter the user name: administrator
Enter the password:

Warning: An account by this name already exists in Active Directory at CN=FAS101,CN=Computers,DC=lab,DC=priv
Ok to reuse this account? {y|n}: y

That’s it!

Note: The CIFS server is automatically set status-admin up after the rename.

Roll back?

If we had to roll back, on the cluster we rename the CIFS server back to what it was:

clu1::*> cifs server modify -vserver FAS101 -status-admin down
clu1::*> cifs server modify -vserver FAS101 -cifs-server FAS101-NEW

Then we re-run cifs setup on the 7-Mode system to get it back on the domain (the output below has been abridged):

FAS101> cifs setup

Do you want to continue and change the current filer account information? [n]: y
(1) Keep the current WINS configuration
Selection (1-3)? 1
This filer is currently configured as a multiprotocol filer. Would you like to reconfigure this filer to be an NTFS-only filer? n
The default name for this CIFS server is 'FAS101'.
Would you like to change this name? n
(1) Active Directory domain authentication (Active Directory domains only)
Selection (1-4)?  1
What is the name of the Active Directory domain? LAB.PRIV
Would you like to configure time services? y
Enter the time server host(s) and/or address(es)? LAB.PRIV
Would you like to specify additional time servers? n
Enter the name of the Windows user [Administrator@LAB.PRIV]:
Password for Administrator@LAB.PRIV:
CIFS - Logged in as Administrator@LAB.PRIV.
An account that matches the name 'FAS101' already exists in Active Directory: 'cn=fas101,cn=computers,dc=lab,dc=priv'. This is normal if you are re-running CIFS Setup. You may continue by using this account or changing the name of this CIFS server.
Do you want to re-use this machine account? y
CIFS - Starting SMB protocol...

Scenario 2: Maintaining NETBIOS in Multi-1 Transitions

If we’re consolidating pFilers/vFilers to one SVM, but still want to keep the NETBIOS names, this is where add-netbios-aliases comes in:

clu1::> cifs server add-netbios-aliases -vserver FAS101 -netbios-aliases FAS102,FAS103,FAS104,FAS105
clu1::> cifs server show -vserver FAS101 -fields netbios-aliases,cifs-server
vserver cifs-server netbios-aliases
------- ----------- ---------------------------
FAS101  FAS101      FAS102,FAS103,FAS104,FAS105


  1. I know this is an old post, I came across this after lots of searching. Why doesn't Netapp provide this as a valid solution to change the NETBIOS name on CDOT. Is it a case where it works perfectly fine, but Netapp doesn't "support" this method? Thanks!

    1. Hello Rich,

      If you have a reason to use it post a 7 to C cutover (before clients have connected), or it's part of a DR procedure, or it's a test/new-build system that was given the wrong/a temp name - I can't see anything wrong with using it. It's never going to be used in a live production environment since it would be quite disruptive (which might be why it's hidden down at diag.)