Re: [Veritas-bu] VTL with NDMP
Yes, I've found the same; with direct NDMP, the SIZE_DATA_BUFFERS_NDMP must match, however, three-way NDMP is less picky. On 7/5/07, Adams, Dwayne <[EMAIL PROTECTED]> wrote: > I did some testing with SIZE_DATA_BUFFERS_NDMP using direct attached and > I think the setting is not used by my filer, but the buffers size you > set must match the buffer size in the filer configuration. So there is > a connection between this setting and the local filer buffer size. If > they don't match I get I/O errors. > > Dwayne Adams > > -Original Message- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Curtis > Preston > Sent: Thursday, July 05, 2007 11:32 AM > To: Nick Majeran; Dellaripa, Rich > Cc: Rajmund Siwik; veritas-bu@mailman.eng.auburn.edu > Subject: Re: [Veritas-bu] VTL with NDMP > > I _BELIEVE_ that SIZE_DATA_BUFFERS_NDMP applies only to 3rd party NDMP > backups that are sent to a NetBackup server. If you're doing filer to > self or filer to filer backups (3rd party backups to another filer), > then I don't think that SIZE_DATA_BUFFERS_NDMP applies. When NetBackup > is telling a filer to dump to himself or to another filer, I believe the > only thing it does it begin the process and then stand back and wait for > it to finish, and for the NDMP server tell the NetBackup server what it > backed up. > > --- > W. Curtis Preston > Backup Blog @ www.backupcentral.com > VP Data Protection, GlassHouse Technologies > > -Original Message- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Nick > Majeran > Sent: Thursday, July 05, 2007 7:10 PM > To: Dellaripa, Rich > Cc: Rajmund Siwik; veritas-bu@mailman.eng.auburn.edu > Subject: Re: [Veritas-bu] VTL with NDMP > > Again, let me reiterate: I have not attempted to tune NDMP backups > from a NetApp filer to LTO-3 tape. All of my tests were conducted > from EMC Celerra NSX NAS devices. > > However, one thing you should be able to tune, and which is quite > easy, is SIZE_DATA_BUFFERS_NDMP. By default, Netbackup uses a 63k > block size for NDMP based backups. Obviously, increasing that from > the default to something more practical, like say (256k), increases > speed writing to tape. LTO-3 supports a maximum block size of > 2097152 bytes. > > On a Celerra, you can configure the PAX parameters below: > > param_name facility default current > configured > paxWriteBuff PAX 64 64 > dump PAX 0 0 > allowVLCRestoreToUFS PAX 0 0 > checkUtf8Filenames PAX 1 1 > paxStatBuff PAX128128 > readWriteBlockSizeInKB PAX 64 64 > filter.numFileFilter PAX 5 5 > paxReadBuff PAX 64 64 > filter.numDirFilter PAX 5 5 > noFileStreamsPAX 0 0 > nFTSThreads PAX 8 8 > scanOnRestorePAX 1 1 > filter.caseSensitive PAX 1 1 > nPrefetchPAX 8 8 > nRestore PAX 16 16 > writeToArch PAX 1 1 > writeToTape PAX 1 1 > nThread PAX 64 64 > > So, there are quite a few parameters to configure from a NDMP > standpoint on a Celerra. > > -- nick > > On 7/5/07, Dellaripa, Rich <[EMAIL PROTECTED]> wrote: > > I second that inquiry...it was my understanding there wasn't much you > > could do to tune NDMP backups. > > > > ---Rich Dellaripa > > > > -Original Message- > > From: Rajmund Siwik [mailto:[EMAIL PROTECTED] > > Sent: Tuesday, July 03, 2007 4:35 PM > > To: Nick Majeran; veritas-bu@mailman.eng.auburn.edu > > Subject: Re: [Veritas-bu] VTL with NDMP > > > > What kind of tuning you are doing on NetApps to get that speed? > > > > > > > > I have newer and older Net App boxes, assuming a 2GB san, what > > performance can I expect using NDMP? > > > > > Out of the box, untuned, 50-80 MB/s to LTO-3. Tuned, 70-160 MB/s. > > > > > > -- nick > > > > > > > > Thanks in advance! > > > > > > Paul Kenny > > > > > > > > > +-
Re: [Veritas-bu] VTL with NDMP
I did some testing with SIZE_DATA_BUFFERS_NDMP using direct attached and I think the setting is not used by my filer, but the buffers size you set must match the buffer size in the filer configuration. So there is a connection between this setting and the local filer buffer size. If they don't match I get I/O errors. Dwayne Adams -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Curtis Preston Sent: Thursday, July 05, 2007 11:32 AM To: Nick Majeran; Dellaripa, Rich Cc: Rajmund Siwik; veritas-bu@mailman.eng.auburn.edu Subject: Re: [Veritas-bu] VTL with NDMP I _BELIEVE_ that SIZE_DATA_BUFFERS_NDMP applies only to 3rd party NDMP backups that are sent to a NetBackup server. If you're doing filer to self or filer to filer backups (3rd party backups to another filer), then I don't think that SIZE_DATA_BUFFERS_NDMP applies. When NetBackup is telling a filer to dump to himself or to another filer, I believe the only thing it does it begin the process and then stand back and wait for it to finish, and for the NDMP server tell the NetBackup server what it backed up. --- W. Curtis Preston Backup Blog @ www.backupcentral.com VP Data Protection, GlassHouse Technologies -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Nick Majeran Sent: Thursday, July 05, 2007 7:10 PM To: Dellaripa, Rich Cc: Rajmund Siwik; veritas-bu@mailman.eng.auburn.edu Subject: Re: [Veritas-bu] VTL with NDMP Again, let me reiterate: I have not attempted to tune NDMP backups from a NetApp filer to LTO-3 tape. All of my tests were conducted from EMC Celerra NSX NAS devices. However, one thing you should be able to tune, and which is quite easy, is SIZE_DATA_BUFFERS_NDMP. By default, Netbackup uses a 63k block size for NDMP based backups. Obviously, increasing that from the default to something more practical, like say (256k), increases speed writing to tape. LTO-3 supports a maximum block size of 2097152 bytes. On a Celerra, you can configure the PAX parameters below: param_name facility default current configured paxWriteBuff PAX 64 64 dump PAX 0 0 allowVLCRestoreToUFS PAX 0 0 checkUtf8Filenames PAX 1 1 paxStatBuff PAX128128 readWriteBlockSizeInKB PAX 64 64 filter.numFileFilter PAX 5 5 paxReadBuff PAX 64 64 filter.numDirFilter PAX 5 5 noFileStreamsPAX 0 0 nFTSThreads PAX 8 8 scanOnRestorePAX 1 1 filter.caseSensitive PAX 1 1 nPrefetchPAX 8 8 nRestore PAX 16 16 writeToArch PAX 1 1 writeToTape PAX 1 1 nThread PAX 64 64 So, there are quite a few parameters to configure from a NDMP standpoint on a Celerra. -- nick On 7/5/07, Dellaripa, Rich <[EMAIL PROTECTED]> wrote: > I second that inquiry...it was my understanding there wasn't much you > could do to tune NDMP backups. > > ---Rich Dellaripa > > -Original Message- > From: Rajmund Siwik [mailto:[EMAIL PROTECTED] > Sent: Tuesday, July 03, 2007 4:35 PM > To: Nick Majeran; veritas-bu@mailman.eng.auburn.edu > Subject: Re: [Veritas-bu] VTL with NDMP > > What kind of tuning you are doing on NetApps to get that speed? > > > > > I have newer and older Net App boxes, assuming a 2GB san, what > performance can I expect using NDMP? > > > Out of the box, untuned, 50-80 MB/s to LTO-3. Tuned, 70-160 MB/s. > > > -- nick > > > > > Thanks in advance! > > > > Paul Kenny > > > > > +-- > > |This was sent by [EMAIL PROTECTED] via Backup Central. > > |Forward SPAM to [EMAIL PROTECTED] > > > +-- > ___ > Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu > http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu > > Conexant E-mail Firewall (Conexant.Com) made the following > annotations- > ** Legal Disclaimer > > > "This email may contain confidential and privileged material for the > so
Re: [Veritas-bu] VTL with NDMP
I _BELIEVE_ that SIZE_DATA_BUFFERS_NDMP applies only to 3rd party NDMP backups that are sent to a NetBackup server. If you're doing filer to self or filer to filer backups (3rd party backups to another filer), then I don't think that SIZE_DATA_BUFFERS_NDMP applies. When NetBackup is telling a filer to dump to himself or to another filer, I believe the only thing it does it begin the process and then stand back and wait for it to finish, and for the NDMP server tell the NetBackup server what it backed up. --- W. Curtis Preston Backup Blog @ www.backupcentral.com VP Data Protection, GlassHouse Technologies -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Nick Majeran Sent: Thursday, July 05, 2007 7:10 PM To: Dellaripa, Rich Cc: Rajmund Siwik; veritas-bu@mailman.eng.auburn.edu Subject: Re: [Veritas-bu] VTL with NDMP Again, let me reiterate: I have not attempted to tune NDMP backups from a NetApp filer to LTO-3 tape. All of my tests were conducted from EMC Celerra NSX NAS devices. However, one thing you should be able to tune, and which is quite easy, is SIZE_DATA_BUFFERS_NDMP. By default, Netbackup uses a 63k block size for NDMP based backups. Obviously, increasing that from the default to something more practical, like say (256k), increases speed writing to tape. LTO-3 supports a maximum block size of 2097152 bytes. On a Celerra, you can configure the PAX parameters below: param_name facility default current configured paxWriteBuff PAX 64 64 dump PAX 0 0 allowVLCRestoreToUFS PAX 0 0 checkUtf8Filenames PAX 1 1 paxStatBuff PAX128128 readWriteBlockSizeInKB PAX 64 64 filter.numFileFilter PAX 5 5 paxReadBuff PAX 64 64 filter.numDirFilter PAX 5 5 noFileStreamsPAX 0 0 nFTSThreads PAX 8 8 scanOnRestorePAX 1 1 filter.caseSensitive PAX 1 1 nPrefetchPAX 8 8 nRestore PAX 16 16 writeToArch PAX 1 1 writeToTape PAX 1 1 nThread PAX 64 64 So, there are quite a few parameters to configure from a NDMP standpoint on a Celerra. -- nick On 7/5/07, Dellaripa, Rich <[EMAIL PROTECTED]> wrote: > I second that inquiry...it was my understanding there wasn't much you > could do to tune NDMP backups. > > ---Rich Dellaripa > > -Original Message- > From: Rajmund Siwik [mailto:[EMAIL PROTECTED] > Sent: Tuesday, July 03, 2007 4:35 PM > To: Nick Majeran; veritas-bu@mailman.eng.auburn.edu > Subject: Re: [Veritas-bu] VTL with NDMP > > What kind of tuning you are doing on NetApps to get that speed? > > > > > I have newer and older Net App boxes, assuming a 2GB san, what > performance can I expect using NDMP? > > > Out of the box, untuned, 50-80 MB/s to LTO-3. Tuned, 70-160 MB/s. > > > -- nick > > > > > Thanks in advance! > > > > Paul Kenny > > > > > +-- > > |This was sent by [EMAIL PROTECTED] via Backup Central. > > |Forward SPAM to [EMAIL PROTECTED] > > > +-- > ___ > Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu > http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu > > Conexant E-mail Firewall (Conexant.Com) made the following > annotations- > ** Legal Disclaimer > > > "This email may contain confidential and privileged material for the > sole use of the intended recipient. Any unauthorized review, use or > distribution by others is strictly prohibited. If you have received the > message in error, please advise the sender by reply email and delete the > message. Thank you." > > ** > > - > > > ___ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu ___ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu
Re: [Veritas-bu] VTL with NDMP
EMC actually has a whole written guide to tuning the Celerra. You can get it off of powerlink. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Nick Majeran Sent: Thursday, July 05, 2007 2:10 PM To: Dellaripa, Rich Cc: Rajmund Siwik; veritas-bu@mailman.eng.auburn.edu Subject: Re: [Veritas-bu] VTL with NDMP Again, let me reiterate: I have not attempted to tune NDMP backups from a NetApp filer to LTO-3 tape. All of my tests were conducted from EMC Celerra NSX NAS devices. However, one thing you should be able to tune, and which is quite easy, is SIZE_DATA_BUFFERS_NDMP. By default, Netbackup uses a 63k block size for NDMP based backups. Obviously, increasing that from the default to something more practical, like say (256k), increases speed writing to tape. LTO-3 supports a maximum block size of 2097152 bytes. On a Celerra, you can configure the PAX parameters below: param_name facility default current configured paxWriteBuff PAX 64 64 dump PAX 0 0 allowVLCRestoreToUFS PAX 0 0 checkUtf8Filenames PAX 1 1 paxStatBuff PAX128128 readWriteBlockSizeInKB PAX 64 64 filter.numFileFilter PAX 5 5 paxReadBuff PAX 64 64 filter.numDirFilter PAX 5 5 noFileStreamsPAX 0 0 nFTSThreads PAX 8 8 scanOnRestorePAX 1 1 filter.caseSensitive PAX 1 1 nPrefetchPAX 8 8 nRestore PAX 16 16 writeToArch PAX 1 1 writeToTape PAX 1 1 nThread PAX 64 64 So, there are quite a few parameters to configure from a NDMP standpoint on a Celerra. -- nick On 7/5/07, Dellaripa, Rich <[EMAIL PROTECTED]> wrote: > I second that inquiry...it was my understanding there wasn't much you > could do to tune NDMP backups. > > ---Rich Dellaripa > > -Original Message- > From: Rajmund Siwik [mailto:[EMAIL PROTECTED] > Sent: Tuesday, July 03, 2007 4:35 PM > To: Nick Majeran; veritas-bu@mailman.eng.auburn.edu > Subject: Re: [Veritas-bu] VTL with NDMP > > What kind of tuning you are doing on NetApps to get that speed? > > > > > I have newer and older Net App boxes, assuming a 2GB san, what > performance can I expect using NDMP? > > > Out of the box, untuned, 50-80 MB/s to LTO-3. Tuned, 70-160 MB/s. > > > -- nick > > > > > Thanks in advance! > > > > Paul Kenny > > > > > +-- > > |This was sent by [EMAIL PROTECTED] via Backup Central. > > |Forward SPAM to [EMAIL PROTECTED] > > > +-- > ___ > Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu > http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu > > Conexant E-mail Firewall (Conexant.Com) made the following > annotations- > ** Legal Disclaimer > > > "This email may contain confidential and privileged material for the > sole use of the intended recipient. Any unauthorized review, use or > distribution by others is strictly prohibited. If you have received the > message in error, please advise the sender by reply email and delete the > message. Thank you." > > ** > > - > > > ___ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu ___ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu
Re: [Veritas-bu] VTL with NDMP
Again, let me reiterate: I have not attempted to tune NDMP backups from a NetApp filer to LTO-3 tape. All of my tests were conducted from EMC Celerra NSX NAS devices. However, one thing you should be able to tune, and which is quite easy, is SIZE_DATA_BUFFERS_NDMP. By default, Netbackup uses a 63k block size for NDMP based backups. Obviously, increasing that from the default to something more practical, like say (256k), increases speed writing to tape. LTO-3 supports a maximum block size of 2097152 bytes. On a Celerra, you can configure the PAX parameters below: param_name facility default current configured paxWriteBuff PAX 64 64 dump PAX 0 0 allowVLCRestoreToUFS PAX 0 0 checkUtf8Filenames PAX 1 1 paxStatBuff PAX128128 readWriteBlockSizeInKB PAX 64 64 filter.numFileFilter PAX 5 5 paxReadBuff PAX 64 64 filter.numDirFilter PAX 5 5 noFileStreamsPAX 0 0 nFTSThreads PAX 8 8 scanOnRestorePAX 1 1 filter.caseSensitive PAX 1 1 nPrefetchPAX 8 8 nRestore PAX 16 16 writeToArch PAX 1 1 writeToTape PAX 1 1 nThread PAX 64 64 So, there are quite a few parameters to configure from a NDMP standpoint on a Celerra. -- nick On 7/5/07, Dellaripa, Rich <[EMAIL PROTECTED]> wrote: > I second that inquiry...it was my understanding there wasn't much you > could do to tune NDMP backups. > > ---Rich Dellaripa > > -Original Message- > From: Rajmund Siwik [mailto:[EMAIL PROTECTED] > Sent: Tuesday, July 03, 2007 4:35 PM > To: Nick Majeran; veritas-bu@mailman.eng.auburn.edu > Subject: Re: [Veritas-bu] VTL with NDMP > > What kind of tuning you are doing on NetApps to get that speed? > > > > > I have newer and older Net App boxes, assuming a 2GB san, what > performance can I expect using NDMP? > > > Out of the box, untuned, 50-80 MB/s to LTO-3. Tuned, 70-160 MB/s. > > > -- nick > > > > > Thanks in advance! > > > > Paul Kenny > > > > > +-- > > |This was sent by [EMAIL PROTECTED] via Backup Central. > > |Forward SPAM to [EMAIL PROTECTED] > > > +-- > ___ > Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu > http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu > > Conexant E-mail Firewall (Conexant.Com) made the following > annotations- > ** Legal Disclaimer > > > "This email may contain confidential and privileged material for the > sole use of the intended recipient. Any unauthorized review, use or > distribution by others is strictly prohibited. If you have received the > message in error, please advise the sender by reply email and delete the > message. Thank you." > > ** > > - > > > ___ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu
Re: [Veritas-bu] VTL with NDMP
I second that inquiry...it was my understanding there wasn't much you could do to tune NDMP backups. ---Rich Dellaripa -Original Message- From: Rajmund Siwik [mailto:[EMAIL PROTECTED] Sent: Tuesday, July 03, 2007 4:35 PM To: Nick Majeran; veritas-bu@mailman.eng.auburn.edu Subject: Re: [Veritas-bu] VTL with NDMP What kind of tuning you are doing on NetApps to get that speed? > > I have newer and older Net App boxes, assuming a 2GB san, what performance can I expect using NDMP? > Out of the box, untuned, 50-80 MB/s to LTO-3. Tuned, 70-160 MB/s. -- nick > > Thanks in advance! > > Paul Kenny > > +-- > |This was sent by [EMAIL PROTECTED] via Backup Central. > |Forward SPAM to [EMAIL PROTECTED] > +-- ___ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu Conexant E-mail Firewall (Conexant.Com) made the following annotations- ** Legal Disclaimer "This email may contain confidential and privileged material for the sole use of the intended recipient. Any unauthorized review, use or distribution by others is strictly prohibited. If you have received the message in error, please advise the sender by reply email and delete the message. Thank you." ** - ___ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu
Re: [Veritas-bu] VTL with NDMP
We haven't tested at all with NetApp, unfortunately. EMC Celerra with DMX disk on the back has been our NDMP mule, along with NBU 6 NDMP SSO and fc LTO-3 as the target. We tested a few VTL vendors (who shall remain unnamed), and found similar results. On 7/3/07, Rajmund Siwik <[EMAIL PROTECTED]> wrote: > What kind of tuning you are doing on NetApps to get that speed? > > > > > I have newer and older Net App boxes, assuming a 2GB san, what > performance can I expect using NDMP? > > > Out of the box, untuned, 50-80 MB/s to LTO-3. Tuned, 70-160 MB/s. > > > -- nick > > > > > Thanks in advance! > > > > Paul Kenny > > > > > +-- > > |This was sent by [EMAIL PROTECTED] via Backup Central. > > |Forward SPAM to [EMAIL PROTECTED] > > > +-- > ___ > Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu > http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu > > Conexant E-mail Firewall (Conexant.Com) made the following > annotations-** > Legal Disclaimer > > "This email may contain confidential and privileged material for the sole > use of the intended recipient. Any unauthorized review, use or distribution > by others is strictly prohibited. If you have received the message in error, > please advise the sender by reply email and delete the message. Thank you." > > ** > > - > ___ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu
Re: [Veritas-bu] VTL with NDMP
What kind of tuning you are doing on NetApps to get that speed? > > I have newer and older Net App boxes, assuming a 2GB san, what performance can I expect using NDMP? > Out of the box, untuned, 50-80 MB/s to LTO-3. Tuned, 70-160 MB/s. -- nick > > Thanks in advance! > > Paul Kenny > > +-- > |This was sent by [EMAIL PROTECTED] via Backup Central. > |Forward SPAM to [EMAIL PROTECTED] > +-- ___ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu Conexant E-mail Firewall (Conexant.Com) made the following annotations-** Legal Disclaimer "This email may contain confidential and privileged material for the sole use of the intended recipient. Any unauthorized review, use or distribution by others is strictly prohibited. If you have received the message in error, please advise the sender by reply email and delete the message. Thank you." ** - ___ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu
Re: [Veritas-bu] VTL with NDMP
> Message: 9 > Date: Tue, 03 Jul 2007 08:18:23 -0700 > From: Kenny <[EMAIL PROTECTED]> > Subject: [Veritas-bu] VTL with NDMP > To: VERITAS-BU@mailman.eng.auburn.edu > Message-ID: <[EMAIL PROTECTED]> > > > I am doing some research to see if a VTL will help my NDMP performance. > > Currently I backup my Net App environment over the LAN. I am looking to > improve backup and restore performance. So you are running three-way NDMP right now? Or are you backing up over NFS? > I have a LTO-3 Tape library that can be fiber attached to the Net App filer. > My concern is that the Net App filer will not be able to stream to the tape > drives and I will kill my performance since the tape will have to do lots of > re-positioning and start and stop. > > I was thinking a VTL would be able to match the speed of the net app box > thus the performance would be optimized. LTO-3: 80 MB/s native, 160MB/s compressed. That's pretty fast. VTL: 100-180 MB/s. Make sure your VTL vendor is doing compression in hardware, otherwise turning on compression can reduce your speeds by 50%. We have a very large NDMP (EMC Celerra -> LTO-3) shop here, and I can tell you that very rarely does the backend disk have the horsepower to push LTO-3 much faster than 95 MB/s with real-world tests. With contrived data on a stand-alone Celerra we saw less than a 5% difference between LTO-3 and the VTLs that we were testing. YMMV, of course, but we didn't see a large enough performance advantage to move to VTL. Not only that, but if you are backing up data with long retention periods, be prepared to buy a whole lot of disk for your VTL, unless you will archive off to tape from your VTL. > Questions: > > I have newer and older Net App boxes, assuming a 2GB san, what performance > can I expect using NDMP? > Out of the box, untuned, 50-80 MB/s to LTO-3. Tuned, 70-160 MB/s. >From my experience, VTLs don't really need much tuning, as does tape. They are fast out of the box, but tape can be almost as fast (within 5%) when tuned properly. > Do you see an advantage using VTL in place of multiple LTO-3 drives? Depends on your data. If you are backing up mostly data that is already compressed, you will be limited to the native speed of LTO-3, which is 80 MB/s. A VTL will be faster in that case. However, if your data is mostly uncompressed, then tape is just as fast as VTL. Also, if you have 2 Gb/s coming out of your NetApp, and 2 Gb/s coming into your VTL, the most you are going to see is 240 MB/s. That's three LTO-3 drives. Sure, you can create 16 virtual drives on your VTL, but that's 500% oversubscribed on throughput. > > How many streams are possible (Using NBU 6.x)? Do the number of streams help > in a VTL environment? how about a tape environment? A NetApp filer supports 16 concurrent NDMP sessions at one time. They cannot be muxed, but you can certainly multi-stream to individual drives concurrently. > > Any recommendations on performance tuning with NBU 6 and NDMP? This is more of an issue with tape than VTL. With tape, SIZE_DATA_BUFFERS_NDMP is your friend. HTH. -- nick > > Thanks in advance! > > Paul Kenny > > +-- > |This was sent by [EMAIL PROTECTED] via Backup Central. > |Forward SPAM to [EMAIL PROTECTED] > +-- ___ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu
Re: [Veritas-bu] VTL with NDMP
> I am doing some research to see if a VTL will help my NDMP performance. > > Currently I backup my Net App environment over the LAN. I am looking to > improve backup and restore performance. > > I have a LTO-3 Tape library that can be fiber attached to the Net App > filer. My concern is that the Net App filer will not be able to stream > to the tape drives and I will kill my performance since the tape will > have to do lots of re-positioning and start and stop. Possibly, possibly not. I have a great number of direct attach LTO3 drives in use. While shoeshining is an easy thing to point to and worry about, I find it very difficult to test directly for understanding how much of an impact it has. In general, I've found that my filers under load have bad peformance in all backup cases (even to a null device). The big advantage of a VTL in such cases would be that you're not binding a drive to a filer and making other backups wait for a drive. Of course if you have sufficient drives that they're all directly attached, there may not be a big win. > I have newer and older Net App boxes, assuming a 2GB san, what > performance can I expect using NDMP? All over the board. By default Netapp prefers to serve files over doing system tasks (like NDMP). A filer under heavy load can be brutal for backup times. I've seen one filer go from a 24 hour NDMP backup (to a null device) to under an hour after we killed the load. I don't normally see anything above 80MB/s even to direct attach. If you have 7.2 I think you can use FlexShare to change the priority between user and system requests. I've just now heard of the capability and will be doing some testing in the future. > Do you see an advantage using VTL in place of multiple LTO-3 drives? If you're merging a small number of drives to many filers/streams, then I think it would be an advantage. Filers often take a long period of time during incrementals where they are running the filesystem tree and not sending data. If this is a normal NDMP backup, then the drive is allocated by NBU to the filer the entire time. A VTL can make that dramatically more efficient in incremental runs. For fulls where the Netapp is actually streaming data the whole time, it's probably less of a win. > How many streams are possible (Using NBU 6.x)? Do the number of > streams help in a VTL environment? how about a tape environment? One stream per NDMP target. You can divvy up a volume into multiple targets, but some of the NDMP overhead is shared on the volume. You may not get increased performance if you do that. Most of my backups are one stream per volume. I have a problem volume that is huge that I use multiple streams on to keep the size of the individual images lower. > Any recommendations on performance tuning with NBU 6 and NDMP? Not many. Most of the performance is on the NDMP side. NBU can slow things down if you're doing a lot of backups (especially small files) and the history data going to the catalog has to wait for the NBU master to write the catalog. Speeding up the master could help then. Overloaded filers (near 100% cpu) do slow backups. -- Darren Dunham [EMAIL PROTECTED] Senior Technical Consultant TAOShttp://www.taos.com/ Got some Dr Pepper? San Francisco, CA bay area < This line left intentionally blank to confuse you. > ___ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu
Re: [Veritas-bu] VTL with NDMP
>I have a LTO-3 Tape library that can be fiber attached to the Net App filer. >My concern is that the Net App filer will not be able to stream to the tape >drives and I will kill my performance since the tape will have to do lots >of re-positioning and start and stop. It does heart my good to see somebody thinking about these things. I believe you are probably right. >I was thinking a VTL would be able to match the speed of the net app box >thus the performance would be optimized. That would be correct, sir! >I have newer and older Net App boxes, assuming a 2GB san, what performance >can I expect using NDMP? YMMV. It's a dump thing. >Do you see an advantage using VTL in place of multiple LTO-3 drives? Oh, yeah. NDMP is one of the best uses of VTL. Give each filer as many tape drives as it wants and you don't have to share. Awesome. >How many streams are possible (Using NBU 6.x)? Do the number of streams >help in a VTL environment? how about a tape environment? 1 per drive. That's also an NDMP thing. >Any recommendations on performance tuning with NBU 6 and NDMP? Other than filer filesystem and volume constructioin (and more RAM/CPU), there's not much to do. There's NOTHING to do on the NetBackup side. It's all about the filer, the data, and dump. ___ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu
