How to create 2nd level junction points in name space

[doug_clendening]

I need to mount vols at a junction-path like "/<descriptor>/<vol_name>", but "/<descriptor> doesn't exist.  I don't have a client, so I need to be able to create "/<descriptor>" from the cluster.  It won't mount the vol when junction-path doesn't exist. I get error of "Reason: Junction create failed (2)."  How do I create this empty directory in the vserver name space?

Thanks a bunch.

wdc

[scottgelb]

Justin recently posted a cool way to do this from the OnCommand Unified Manager (DFM) using apitest. Or in his post there was also discussion of nmsdk for the same function without mkdir from a mounted client.

C:\Program Files\MetA[[\DataFabric Manager\DFM\bin> apitest -t filer -h ip -u vsadmin -p password file-create-directory path /path/path/path perm 0777

[parisi]

Yep, thread on this is here:

https://communities.netapp.com/message/103327#103327

Your choices are to create a namespace volume and mount everything to that or to use the workaround posted in the thread with the apitest command.

[doug_clendening]

Thanks a bunch, but I guess I don’t completely understand your post. I have existing vol “us8_01” that I want to mount at “/v01_i254/us8_01”. Actually, I want to mount a dozen vols under “/v01_i254”.)

Here’s what I did:

E:\Program Files\NetApp\DataFabric Manager\DFM\bin>apitest -t filer -h *** -u vsadmin –p ** file-create-directory path /vol/vs01_254/us8_01 perm 0777

Testing: file-create-directory(path=/vol/vs01_i254/us8_01, perm=0777) Failed, errno=13040, reason=Volume vs01_i254 does not exist in Vserver chvpk-vs-nonprod-ora-01. Reason: entry doesn't exist

::> vol create -volume v01_i254 -aggregate aggr_c18_01 -size 20MB -state online -type RW -policy default -unix-permissions ---rwx

[parisi]

So here's what you want to do...

v01_i254 will be your "namespace" - this can be a folder in the vsroot volume or a volume itself.

You already created the volume, but you did not mount it:

::> vol create -volume v01_i254 -aggregate  aggr_c18_01 -size 20MB -state online -type RW -policy default -unix-permissions ---rwx

To mount the volume:

::> vol mount -volume v01_i254 -vserver vservername -junction-path /v01_i254

After you mount the volume to create the namespace, you can then mount whatever you want under it.

So, you could have:

/v01_i254/vol1

/v01_i254/vol2

/v01_i254/vol3

/v01_i254/vol4

and on and on....

But if you wanted to do this:

/v01_i254/vol1/volume

Then you would have to have the following:

/v01_i254

/v01_i254/vol1

The "entry does not exist" means exactly what it says - the folder you want doesn't exist. Think of it from a Windows OS perspective. Can you create a folder called test at C:\folder\test if C:\folder didn't exist?

Let me know if you need more assistance...

[doug_clendening]

Yeah, that’s what I thought and I tried that before I sent the email. However, when I mounted v01_i254 and then tried to mount us8_01.

::> vol show v01_i254 -fields junction-path

(volume show)

vserver volume junction-path

[parisi]

Here's how I did what you want to do:

rr3170c::> vol create -vserver parisi -volume v01_i254 -aggregate aggr2 -size 20MB -state online -type RW  -junction-path /v01_i254

  (volume create)

[Job 7118] Job succeeded: Successful                                                                                                                                  

rr3170c::> vol show -vserver parisi -volume v01_i254 -fields junction-path

  (volume show)

vserver volume   junction-path

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

parisi  v01_i254 /v01_i254

rr3170c::> vol create -vserver parisi -volume clendening -aggregate aggr2 -size 20MB -state online -type RW -policy default -junction-path /v01_i254/clendening

  (volume create)

[Job 7119] Job succeeded: Successful

rr3170c::> vol show -vserver parisi -volume clendening -fields junction-path

  (volume show)

vserver volume

junction-path

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

parisi  clendening /v01_i254/clendening

[doug_clendening]

The problem is that “us8_01” already exists and contains data.

What you say works fine for new vols.

::> vol create foo -aggregate aggr_c17_01 -size 20MB -state online -type RW -policy default -unix-permissions ---rwx

[parisi]

Ah then you need to unmount us8_01. That will cause an outage, though.

For example, I have a volume called UNIX that I want to mount.

rr3170c::> vol show -vserver parisi -volume unix -fields junction-path

  (volume show)

vserver volume junction-path

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

parisi  unix   /unix 

rr3170c::> vol mount -vserver parisi -volume unix -junction-path /v01_i254/clendening/unix

  (volume mount)

Error: command failed: Volume 'unix' on Vserver 'parisi' is mounted at '/unix'.

rr3170c::> vol unmount -vserver parisi -volume unix

  (volume unmount)

rr3170c::> vol show -vserver parisi -volume unix -fields junction-path                   

  (volume show)

vserver volume junction-path

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

parisi  unix   -            

rr3170c::> vol mount -vserver parisi -volume unix -junction-path /v01_i254/clendening/unix

  (volume mount)

rr3170c::> vol show -vserver parisi -volume unix -fields junction-path                   

  (volume show)

vserver volume junction-path            

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

parisi  unix   /v01_i254/clendening/unix

[doug_clendening]

There is seems to be something going on in my cluster that’s different from yours. I made sure both vols were unmounted. I then successfully mounted “v01_i254”, but get the same error when I try to mount “us8_01” volume underneath. Did I mess something up when I ran “apitest * file-create-directory path *” when v01_i254 wasn’t mounted?

chvpk-cmode-nonprod-oracle::> vol show v01_i254 -fields junction-path

(volume show)

vserver volume junction-path

[parisi]

Your output is not showing up properly in the thread, so I don't know exactly what is happening.

It's possible that the apitest created something you didn't necessarily want.

What if you try mounting the volume to a different junction?

For example:

vol mount us8_01 /v01_i254/us8_01a

Does that work?

If so, you may have to go into v01_i254 via a client and see if a folder named us8_01 got created and then delete it. Then re-try the mount.

[doug_clendening]

It seems pretty clear that what I did with apitest is the issue. I can mount other volumes under this junction point. The only vol that I can’t mount is the one I referenced in apitest that I ran. I deleted vol “v01_i254” and then recreated. I can now mount “us8_01” at “/v01_i254/us8_01”.

Thanks for all your help. You’ve been most generous.

Doug Clendening

(c) 713-516-4671

[parisi]

No problem. You likely created something that conflicted with what you were trying to use.

Keep in mind that when using apitest that you need to ensure the entire path already exists. Otherwise, you may run into issues.

[doug_clendening]

I can mount one of the volumes that I didn’t run “apitest *” for, in the manner you describe.

chvpk-cmode-nonprod-oracle::> vol mount us8_02 /v01_i254/us8_02

(volume mount)

chvpk-cmode-nonprod-oracle::> vol show us8_02 -fields junction-path

(volume show)

vserver volume junction-path

[scottgelb]

Very good...and thanks to Justin as always and can't say enough about the great support ...back in the GX to c-mode and now Clustered ONTAP all top notch support.

[HENRYPAN2]

Hi Scott,

Which Justin you're thanks for?

Cheers

Henry

[scottgelb]

Parisi. On this thread.

Sent from my iPhone 5

[parisi]

Thanks for the kind words, Scott!

[scottgelb]

One other thought if NFS is enabled in the Vserver is you could use the diag account and mount the Vserver / from the systemshell... then use unix to create the pathing, then umount and exist systemshell.  I don't think this would be ideal for a production system but to have all ideas on how to do this without a client... you would need to run 'sudo mount' from the shell since most commands need root access.