Configuration of AFS for use with DNS

The systems team recently introduced the concept of letting a DNS server determine the AFS database servers via the AFSDB RR.  While this has been practiced quite widely elsewhere, we are now introducting this to BII.  If this means Greek to you, its ok.   What this means for the layman, is, that for the future, there will be zero configuration changes with regards to AFS database servers on the client side, that is what we are aiming to achieve.  This means, that if the network configuration of any of the AFS servers decide to change, we can erect a new one with the same name without asking your permission to change the configuration files.  

Disclaimer: That is provided that we don't change the DNS server itself.

Using AFS to use with DNS:

On Linux platforms (presumably Debian based):

1. Locate where your CellServDB is.  On most systems it is likely to be /etc/openafs, on others, it might be /usr/local/etc/openafs.
   
   
2. Log on as root, on debian based, its 'sudo su', on redhat based, 'su -'.  
   The following commands are assumed that you have been logged in with root access.
   
   
3. Make a backup of your CellServDB.  And create a blank one.
   
   cd <CellServDB> directory
cp CellServDB CellServDB.bak
rm -rf CellServDB
touch CellServDB
   
   
4. Make sure that your 'ThisCell' file reads 'bii.a-star.edu.sg', the AFS cell of BII.
   
   
5. And make sure your afsd client program starts with these flags:
   
   • - afsdb [this makes afsd use the DNS AFSDB RR flag, set on the DNS records for the AFS DB servers]
   • - fakestat [Return fake values for stat calls on cross-cell mounts. This option makes an "ls -l" of /afs much faster since each cell isn't contacted.]
     
   
   
6. Reboot.
   

On Windows:

1. Your CellServDB is in C:\Program Files\OpenAFS\Client\
   
   
2. Make a backup copy of your CellServDB.
   
   
3. Delete and create a blank copy of CellServDB by using Notepad or any other TEXT editor.
   
   
4. Launch your OpenAFS client.  Click on the 'Advanced' tab.  
   
   
   
   
5. Click on the 'AFS Client Configuration' button. Make sure the cell name is shown to be 'bii.a-star.edu.sg'.
   
   
   
   
6. Reboot.

In case of trouble after rebooting:

On Linux platforms:

• As root, cd /var/cache/openafs and remove everything there.  Restart your afs client or reboot.

On Windows:

• WARNING: This is a TRICKY PROCEDURE. So do this with much CARE.  If unsure, please ask the systems team for help.
  
  
• Go to the 'Advanced' tab illustrated earlier. Stop the afs client service by clicking the button highlighted.
  
  
  
  
• Launch regedit via the 'Run' dialog or a command line.
  
  
  
  
• Locate the key under the hierarchy:
  My Computer\HKEY_LOCAL_MACHINE\SOFTWARE\OpenAFS\Client\Freelance
  In there delete all its binary values from 0-3.  
  
  
  
  Do not close the registry editor yet.
  
  
• Restart the AFS client service by going to the 'Advanced' tab and clicking on the button highlighted.
  
  
  
  
• The AFS client wizard will prompt you to enter the cell information and username credentials again.  
  
  
• Go through with it and complete it accurately.  Our BII cell name is 'bii.a-star.edu.sg'.
  
  
• Thereafter, check the registry editor, you should see that 3 binary keys are recreated.
  
  
• Log in to AFS by obtaining tokens.
  
  
  
  
• Verify this with your afs mounted drives that you are able to see them.