FPS France

Just to let everyone interested in know :

- we firstly would make the migration with snapmirror but we figured out that migrating 14x18Gb disks to 7x36Gb disk was impossible (a 13x18G volume - with one 18G spare beside - is tiny larger than a 6x36G volume - just 9G greater :) - so we used ndmp through tapes because we were not sure enought of the NdmpCopy reliability - may I find a tool to validate NdmpCopy in our lab ? :) - when the migration was successful, we installed Snapmirror and obtain a throughput of 20Mb/s :) systems were 5.3.7R3 and models, two F740.

Thank you for all your mail. CU

----- Original Message ----- From: "Van Agt, Cyril" cvanagt@netapp.com To: "Fox, Adam" Adam.Fox@netapp.com; "'FPS France'" fpsfrance@fps.fr Cc: "Mohler, Jeff" jeff.mohler@netapp.com Sent: Thursday, June 28, 2001 12:40 AM Subject: RE: Vol copy max speed ? alternatives ?

Correct. Good use of the WWW ; and a refresh for you old French... ;-)

Cyril

PS : FPS is a NetApp Partner in France.

-----Original Message----- From: Fox, Adam Sent: jeudi 28 juin 2001 00:46 To: Van Agt, Cyril; 'FPS France' Cc: Mohler, Jeff Subject: RE: Vol copy max speed ? alternatives ?

I think this is a close English translation (thanks to Altavista's babelfish service)

In English:

Me I saw SnapMirror making of the 55 MB/s between two F840 via Gigabit. But I do not have experience with of F630 I think that SnapMirror is the best solution in any event. I think that SnapMirror can " be rented " for a migration... Call me if you wish to discuss it.

For Jeff and I who aren't up on our French. :)

-- Adam

-----Original Message----- From: Van Agt, Cyril Sent: Wednesday, June 27, 2001 6:29 PM To: 'FPS France' Cc: Mohler, Jeff; Fox, Adam Subject: RE: Vol copy max speed ? alternatives ?

Moi j'ai vu SnapMirror faire du 55 MB/s entre deux F840 via Gigabit. Mais je n'ai pas d'expérience avec du F630 :-)

Je pense que SnapMirror est la meilleure solution de toute façon. Je pense que SnapMirror peut se "louer" pour une migration... Appelez-moi si vous désirez en discuter.

Cyril Van Agt

Cyril Van Agt mailto:cvanagt@netapp.com Systems Engineer http://www.netapp.com/ Network Appliance France Phone: +33 1.55.20.18.48 42, quai du Point du Jour Fax: +33 1.55.20.18.01 F-92100 BOULOGNE Cell: +33 6.08.85.38.85 ==============================================================

-----Original Message----- From: Mohler, Jeff [mailto:jeff.mohler@netapp.com] Sent: mercredi 27 juin 2001 23:24 To: Fox, Adam; 'FPS France'; toasters@mathworks.com Subject: RE: Vol copy max speed ? alternatives ?

Myself..I havent seen col copy/ndmpcopy/snapmirror do much over 18-22Mb/sec depending on platform.

If I had a free hour Id love to go into my Lab and prove myself wrong, but I wont be able to until at least tomorrow if anyone is interested in some data between some 880s.

-----Original Message----- From: Fox, Adam [mailto:Adam.Fox@netapp.com] Sent: Wednesday, June 27, 2001 1:46 PM To: 'FPS France'; toasters@mathworks.com Subject: RE: Vol copy max speed ? alternatives ?

I guess I'm not sure what a 'perfect' 10BT connection speed is and so the comparisons confuse me.

By my calculations:

10Mb 1MB 1GB 60s 60 min ---- ------- ------ ------- --------- = 4.39 GB/hr. 1s 8Mb 1024MB 1 min 1 hr

This is 10BT at it's maximum throughput...not counting for protocols, etc.

So let's look at 36 GB/hour using the same method:

36GB 1024 MB 8Mb 1 hr 1 min ----- ------------ ------ ------- ---------- = 81.92 Mb/s 1 hr 1 GB 1MB 60 min 60 sec

So you're a little under a "perfect" 100BT from my calcuations. Not great, but not as bad as I read it to be..and 18X better than 10BT.

If the purpose is to reduce downtime (perfectly resonable) then perhaps you need something that can do incremental changes instead of doing it in one shot.

ndmpcopy can help. It's free and has incremental support even if it's a little slower, if you can reduce the size of your last incremental, it won't hurt as much if the data you are trying to move while you are down is smaller.

SnapMirror is *great* for this. The only downside is it is not free. You'll need to work out a deal with your rep if you feel this is really the way you want to go.

Just some thoughts.

-- Adam Fox NetApp Professional Services, NC adamfox@netapp.com

...

-----Original Message----- From: FPS France [mailto:fpsfrance@fps.fr] Sent: Thursday, June 21, 2001 11:20 AM To: toasters@mathworks.com Subject: Vol copy max speed ? alternatives ?

Hi everyone,

We are looking for a high rate migration operation which could let us move a volume from a disk shelf to another. In a first place, we think of using the vol copy command. We thaught we could easily manage a strong volume copy rate but it appeared the rate is buggy limited to 36Gb/hour (as if the Filer was copyinbg over a 'perfect' 10Bas-T interface) : http://now.netapp.com/Knowledgebase/solutionarea.asp?id=3.0.72

95526.2875209& resource= In looking around we found papers dealing with others interface kinds : http://now.netapp.com/Knowledgebase/solutionarea.asp?id=3.0.72

95507.2875209 The limit are 25GB/hr over 100Base-T interface, and 28GB/hr over FDDI so less than a 'perfect' 10Base-T interface. (on a F630 Filer :)

Reasons given by the NetApp support is the CPU has a bunch of work in calculating optimizations of read and write operations. But I would be sure we are really not strunglled by any other limitations.

So here are our two questions : - (just to be sure) did anyone succed in using the vol copy command once and go beyond these limits ? -what is your opinion about that alternative : plug the Filer on a private Giga-ethernet network and make a manual copy (copy -R mnt/nac/vol0 /other_place ) of the whole volume from a shelf to the other. Do you think we could obtain real high rate transfers while keeping the integrity of the volume ? (the volume is a root volume with the "/etc" directory), no special tricks needed (if I use Windows, may I expect ACL modifications) ?

I thank you in advance.