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ron7000
19-Sep-2016, 16:04
I have a few servers on a LAN where I share out the /scratch folder on each via NFS-server,
and then on each server using NFS-client I mount the other's scratch folders.
Problem arises when any one of the servers goes down, for example a reboot.
When an NFS-server is down, I cannot log in to any other system which is an NFS-client to that server.
Specifically:
- an SSH connection to the NFS-client system can be established successfully,
- you can enter your username and password,
- but after entering your password you never get a prompt and the SSH connection is frozen.
- After however long if the NFS-server system finally becomes available, you will get the prompt and be able to use that SSH connection.

How can I make it so that this does not happen?



my /etc/fstab file contains: hpc2:/scratch /scratch_hpc2 nfs defaults 0 0

the /etc/exports file on the nfs-server system contains: /scratch <ip_address>(rw,root_squash,sync,no_subtree_check)

I have set up NFS-server via YAST and I do NOT use NFSv4 nor do I use GSS security,

and /proc/mounts from an nfs-client system shows:

hpc2:/scratch /scratch_hpc2 nfs rw,relatime,vers=3,rsize=1048576,wsize=1048576,nam len=255,hard,proto=tcp,timeo=600,retrans=2,sec=sys ,mountaddr=<ip_address>,mountvers=3,mountport=40551,mountproto=udp,local_ lock=none,addr=<ip_address> 0 0

smflood
19-Sep-2016, 16:58
On 19/09/16 16:14, ron7000 wrote:

> I have a few servers on a LAN where I share out the /scratch folder on
> each via NFS-server,
> and then on each server using NFS-client I mount the other's scratch
> folders.
> Problem arises when any one of the servers goes down, for example a
> reboot.
> When an NFS-server is down, I cannot log in to any other system which is
> an NFS-client to that server.
> Specifically:
> - an SSH connection to the NFS-client system can be established
> successfully,
> - you can enter your username and password,
> - but after entering your password you never get a prompt and the SSH
> connection is frozen.
> - After however long if the NFS-server system finally becomes available,
> you will get the prompt and be able to use that SSH connection.
>
> How can I make it so that this does not happen?
>
>
>
> my /etc/fstab file contains: hpc2:/scratch /scratch_hpc2 nfs
> defaults 0 0
>
> the /etc/exports file on the nfs-server system contains: /scratch
> <ip_address>(rw,root_squash,sync,no_subtree_check)
>
> I have set up NFS-server via YAST and I do NOT use NFSv4 nor do I use
> GSS security,
>
> and /proc/mounts from an nfs-client system shows:
>
> hpc2:/scratch /scratch_hpc2 nfs
> rw,relatime,vers=3,rsize=1048576,wsize=1048576,nam len=255,hard,proto=tcp,timeo=600,retrans=2,sec=sys ,mountaddr=<ip_address>,mountvers=3,mountport=40551,mountproto=udp,local_ lock=none,addr=<ip_address>
> 0 0

Duplicate of
https://forums.suse.com/showthread.php?8241-NFS-client-freezes-when-NFS-server-system-loses-connection

HTH.
--
Simon
SUSE Knowledge Partner

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