Re: NFS Volume Mount Client Listing

chris_mckean · ‎2014-06-04

Hi Guys,

probably a few times a week I get asked "what servers mount that volume" as the mount points on our linux servers are often named differently from the volumes themselves. for example

corporate-websites-htmlt:/vol/CORPWEBSERVICES_HTML

41943040 2183648 39759392 6% /lamp_website_home

So everybody but myself and the other guys who deal with the storage know this volume as '/lamp_website_home' and when I raise an incident around the volume filling up they do not know what I'm talking about. This is where the difficulty comes in. I have no way of saying "check server 1234 as i know that currently has the volume mounted" to point them in the direction of a server currently mounting this volume.

So the only way for them to know what volume I'm raising an incident about is by logging onto a lot of servers to see what the volume is known as in their world. Then they can find out who owns the data in there and chat to them about clearing some out.

So I'm wondering if anyone knows any command or other way to get a lits of what IP's are currently mounting a volume via NFS?

We're currently running OnTAP 8.1.3(CMODE) and 8.2(CMODE) on our clusters.

Cheers

Chris

parisi · ‎2014-06-04

In clustered Data ONTAP, there is a way to see what clients are mounted via NFS, CIFS, etc.

::*> network connections active show -service ?

mount Mount stream protocol

nfs NFS stream protocol

nfs-v2 NFS version 2 stream protocol

nfs-v3 NFS version 3 stream protocol

nlm-v4 Network lock manager stream protocol

sm Session Manager stream protocol

ftp-ctrl FTP control stream protocol

ftp-data FTP data stream protocol

http-1-0 HTTP version 1 stream protocol

http-1-1 HTTP version 1.1 stream protocol

iscsi ISCSI stream protocol

cifs-srv CIFS server stream protocol

cifs-nam CIFS name server stream protocol

loopback loopback stream protocol

rf RC stream protocol

rawscp Raw secure copy stream protocol

discard Descard stream protocol

port-map Port map stream protocol

pass-thru Passthru stream protocol

rclopcp Rc connection stream protocol

nfs-v4 NFS version 4 stream protocol

fcache Flex cache stream protocol

ctlopcp Ct connection stream protocol

rquota Rquota stream protocol

cifs-msrpc CIFS MsRpc stream protocol

unknown unknown protocol

Example:

::*> network connections active show -service nfs*

Vserver Interface Remote

CID Ctx Name Name:Local Port Host:Port Protocol/Service

--------- --- --------- ----------------- -------------------- ----------------

Node: parisi-cdot-02

3461168229 4 flexvol data2:2049 centos64.domain.win2k8.netapp.com:745

TCP/nfs

However, the above does not show you which volume is mounted. But it does help narrow it down...

To see specific information about volumes, turn on per-client stats for NFS:

::> statistics settings modify -display-rates true -client-stats enabled

Warning: System performance may be significantly impacted. Are you sure?

Do you want to continue? {y|n}: y

::> statistics show -object client

Object: client

Instance: 10.228.225.140

Start-time: 6/4/2014 14:47:08

End-time: 6/4/2014 14:47:22

Node: parisi-cdot-02

Counter Value

-------------------------------- --------------------------------

hostname

centos64.domain.win2k8.netapp.com

total-ops 79

nfs3-ops 0

nfs4-ops 0

cifs-ops 79

recv-data 0B

sent-data 23B

recv-packets 3916

sent-packets 0

volumes flexvol:unix

flexvol:rootvol

avg-latency 0us

nlm-ops 0

mount-ops 0

local-ops 0

remote-ops 24

avg-latency-local 0us

avg-latency-remote 0us

danmalcor · ‎2015-09-30

Did the connection between the client and the volume disapear in 8.3?

okieunixsam1 · ‎2016-10-06

I agree I do not see hostname or volume listed in the stats output at all.

@danmalcor wrote:
Did the connection between the client and the volume disapear in 8.3?

DOUGLASSIGGINS · ‎2016-04-26

Greetings,

Like Dan I also do not see a way to do nfsstats by client in 8.3, coming back to cmode (Justin probably remembers me from GX) I'd assumed this part was done. Is there another option I should be looking for in ngsh (or whatever this new cmode shell is called now)?

I can however still run nperf and pcpconfig, and I dont think I have to convert hex anymore.

DPOLEARY1 · ‎2017-06-21

I too am desparate for a simple way of listing out what clients are connecting to what volumes. In 7-mode, you could look in /etc/rmtab to get a list, and although it wasn't 100% accurate (it often listed clietns after they disconnect), it was a huge help. I wouldn't think this should be that difficult to implement. On any linux box running an NFS server, I can run a "showmount -a" to get a list of clients and what nfs exports each is mounting. Migrations are very difficult when I have to take educated guesses on which clients will be affected. If anyone else has any methods of obtaining this information, please share. I'll keep searching and also post anything I find.

parisi · ‎2017-10-24

There is currently no way to do this today. I've been leaning on engineering to include this in a future version of ONTAP.

Jim_Robertson · ‎2017-11-10

I'm guessing this also means there is no way to tell if an NFS connection is encrypted or not?

For SMB (using OnTap 9.1), I use this command to get a lot of useful information about all the connections to my cluster:
cifs session show -fields node,vserver,lif-address,address,windows-user,auth-mechanism,shares,protocol-version,is-session-signed,smb-encryption-status

This is the closest I've been able to come to it for NFS. It shows me the servers and the LIFs they are connecting to, but I see no way to correlate this to a particular volume.

network connections active show -node * -service NFS* -fields node,cid,vserver,lif-name,local-address,local-port,remote-ip,remote-host,remote-port

Nate_Hudson · ‎2017-11-30

Is there any update to this thread? I've tried this process on a system running 9.1P2, and there is still no correlation between volume and hostname.

yuvaraja · ‎2018-07-11

nfs modify -vserver vserver_name -showmount enabled
showmount -e (filerIP)
/test1 (everyone)
/test1/qtree1 (everyone)
/test1/qtree2 (everyone)

showmount -a vserverIP ...check with this command once..

DPOLEARY1 · ‎2018-07-12

Thanks yuvaraja, but this does not provide a list of clients that are accessing a particular share.This just shows what exports are available. I need to be able to generate a list of clients that are currently mounting some export path (ex. /export), similar to what you would get by running "showmount -a" on a linux machine with an nfs server running.

Henrik_Aicher · ‎2019-01-21

Hi,

if you have a 1:1 relationship between Export and Lif,

why not use:
net connections active show -lif-name <name> -inst

Cheers,

Henrik

danmalcor · ‎2019-01-21

@Henrik_Aicher wrote:

Hi,

if you have a 1:1 relationship between Export and Lif,

why not use:
net connections active show -lif-name <name> -inst

Cheers,

Henrik

Of course having 500 LIFs has it’s own problems.

DPOLEARY1 · ‎2019-01-21

Hi,

Thanks, but no we don't have a 1:1 relationship between exports and LIFs. I doubt that's a common configuration. On a typical system we may have 50 or so exports and mabye 5 LIFs.

There's still no great solution apparently. I usually have to run:

network connections active show -service nfs

which returns a list of clients. Then if I'm looking for a specific export, I run a script which goes out to every client in that list and check if it's mounting that export. It's a lot of work to gather information that should be available with a simple command imo.

Vidhs · ‎2020-01-23

Just learnt that the ability to map NFS clients to specific volume and IP addresses are being introduced from ontap 9.7, something like this. As ontap 9.7 is just released, will be interesting to look into this availability :

cluster::> nfs connected-clients show ?
  [ -instance | -fields <fieldname>, ... ]
  [[-node] <nodename>]                                               Node Name
  [[-vserver] <vserver>]                                             Vserver
  [[-data-lif-ip] <IP Address>]                                      Data LIF IP Address
  [[-client-ip] <IP Address>]                                        Client IP Address
  [[-volume] <volume name>]                                          Volume Accessed
  [[-protocol] <Client Access Protocol>]                             Protocol Version
  [ -idle-time <[<integer>d][<integer>h][<integer>m][<integer>s]> ]  Idle Time (Sec)
  [ -local-reqs <integer> ]                                          Number of Local Reqs
  [ -remote-reqs <integer> ]                                         Number of Remote Reqs

Jim_Robertson · ‎2020-01-24

@Vidhs wrote:

Just learnt that the ability to map NFS clients to specific volume and IP addresses are being introduced from ontap 9.7, something like this. As ontap 9.7 is just released, will be interesting to look into this availability :

Thanks, @Vidhs !

Here's a brief overview they did as part of the Tech OnTap podcast:

https://whyistheinternetbroken.wordpress.com/2019/11/08/ontap97-feature-sneak-peek-nfs-client-to-volume-mapping/

I, for one, am very glad to see that this has been added.