Re: NFS mount requests going though the Virtual Interface (655 Views)
Reply
Honored Contributor
Naveej.K.A
Posts: 820
Registered: ‎06-11-2003
Message 1 of 6 (661 Views)

NFS mount requests going though the Virtual Interface

Scenario:-

An NFS Server, server exports an NFS filesystem called /ignitebkp to an NFS client, client.  Share rw access & mount access are given to client only.  

 

The client has a primary interface (lan26) and multiple virtual interfaces (Yes, service guard packages).  

 

Problem:-

mount permission denied on client.  On examining the mountd.log on server, I see that the requests to mount are coming from the virtual interface and not from the IP address of client.  How can I get the client to send the request for mount and all future access through its primary interface which actually resolves to client in DNS?


practice makes a man perfect!!!
HP Pro
Dave Olker
Posts: 1,432
Registered: ‎10-10-2002
Message 2 of 6 (655 Views)

Re: NFS mount requests going though the Virtual Interface

Are you saying there are multiple IP interfaces on the same subnet?  If not, this is a matter of selecting the proper NFS server IP address that routes through the appropriate client interface. If your NFS client has numerous IP interfaces on the same subnet, that gets a little trickier to force the client to send using a specific interface.  

 

If you want the client to send mount requests using the primary IP address of the interface you can try experimenting with the kctune parameter ip_strong_es_model. A setting of 2 might give you the behavior you're looking for.

 

Dave

Honored Contributor
Naveej.K.A
Posts: 820
Registered: ‎06-11-2003
Message 3 of 6 (647 Views)

Re: NFS mount requests going though the Virtual Interface

Hi Dave.

 

Thanks for your reply.  

 

Yes, I have multiple interfaces (one physical & many virtual) which are on the same subnet.  These virtual interfaces are my service guard package IP addresses.  

 

From your reply, it looks like a common behavior.  I would like to know who & what determines which IP address should send the mount request.  Meanwhile, I will do some study on ip_strong_es_model and will test it.  

 

But, I am curious to know if this random selection is a known behavior.

 

Regards,

Naveej

practice makes a man perfect!!!
HP Pro
Dave Olker
Posts: 1,432
Registered: ‎10-10-2002
Message 4 of 6 (626 Views)

Re: NFS mount requests going though the Virtual Interface


Naveej.K.A wrote: 

But, I am curious to know if this random selection is a known behavior.


I very much doubt this is a "random" selection.  More likely it is selecting the best interface to use based on the IP routing tables.  You can verify this by examining the routing tables via "netstat -rn".  You can also manipulate the routing tables to try to get the preferred interface used during NFS mounts, though I would first experiment with ip_strong_es_model.

 

Dave

Honored Contributor
Naveej.K.A
Posts: 820
Registered: ‎06-11-2003
Message 5 of 6 (613 Views)

Re: NFS mount requests going though the Virtual Interface

Dave, Thanks for following up.

 

Well, I have a default gateway for the entire subnet.  Both the physical & the virtual interface are on the same subnet, so I guess the routing information is not being used to pick up which interface the client must use.  

 

To make it clear.

 

10.209.11.82   client       client.domain.com  ---> plumbed on lan26
10.209.11.89   client6      client6.domain.com ---> plumbed on lan26:4
 
10.209.11.16   server       server.domain.com

 

 

client & server resolve to the hostname in DNS.  whereas, client6 is my package name.  The request for mount is going from client6instead of client.  

 

I can give access permission in my dfstab for client6, but the whole thing will break when my package moves from client toanotherclient.

practice makes a man perfect!!!
HP Pro
Rajesh K Chaurasia
Posts: 76
Registered: ‎01-31-2008
Message 6 of 6 (573 Views)

Re: NFS mount requests going though the Virtual Interface

Not sure if this HP-UX routing gray paper (NOT an official HP document) could be of some help in routing in multi-homed environments.

 

http://www.mayoxide.com/presentations/Understanding_hpux_routing.pdf

 

Regards

-Rajesh

The opinions expressed above are the personal opinions of the authors, not of HP. By using this site, you accept the Terms of Use and Rules of Participation.