NAS vs traditional fileservers
We currently use traditional windows fileservers, but are being presented with an opportunity to start using a NAS device. I've been reading up on NDMP, doesn't sound to me like NAS is the backup admin's friend. Can anyone who has gone down this road share any of the biggest pros/cons/gotchas? I seem to recall from several years ago that getting the backup data offsite was an issue, but the NAS vendor claims this is no longer true. Currently using half a dozen fileservers to manage about 20TB of user data. Thanks, Steve Schaub Systems Engineer, Windows BlueCross BlueShield of Tennessee - Please see the following link for the BlueCross BlueShield of Tennessee E-mail disclaimer: http://www.bcbst.com/email_disclaimer.shtm
Re: NAS vs traditional fileservers
We've been backing up one NAS system with NDMP filer-to-server for about 2 years now, it's currently at around 16TB. In our particular setup, we rely on backups fitting on disk before going to tape. As such, we've had to size the disk pool for that client to match the NAS size. We hit a problem recently when they grew one filesystem to 10TB. IBM developers found an 8.7TB size limit in disk pools, so backups were going directly to tape and being preempted by the morning migrations. We got around this by backing up to virtual volumes on another instance with a large disk pool. Of course NDMP backups are full/differentials, so the retention policies you're used to are pretty much out the window. If it's a NetApp device, you can back it up with a regular TSM client using the snapdiff option. Even given the limitations of CIFS (slw), in my limited testing I've found the savings from not having to do full/differentials to be a big win. There's also a savings in tape occupancy, since files that haven't changed aren't backed up again. Clients charge on occupancy, like ours, like this. I'm not sure what you mean about getting data offsite, but we're able to do our normal copy pools with NDMP backups. - Cameron Hanover chano...@umich.edu When any government, or church for that matter, undertakes to say to its subjects, this you may not read, this you must not see, this you are forbidden to know, the end result is tyranny and oppression, no matter how holy the motive. --Robert A. Heinlein On Jun 23, 2010, at 11:39 AM, Schaub, Steve wrote: We currently use traditional windows fileservers, but are being presented with an opportunity to start using a NAS device. I've been reading up on NDMP, doesn't sound to me like NAS is the backup admin's friend. Can anyone who has gone down this road share any of the biggest pros/cons/gotchas? I seem to recall from several years ago that getting the backup data offsite was an issue, but the NAS vendor claims this is no longer true. Currently using half a dozen fileservers to manage about 20TB of user data. Thanks, Steve Schaub Systems Engineer, Windows BlueCross BlueShield of Tennessee - Please see the following link for the BlueCross BlueShield of Tennessee E-mail disclaimer: http://www.bcbst.com/email_disclaimer.shtm
Re: NAS vs traditional fileservers
We are in the same situation - possibly changing from Win Servers (using some kind of microsoft replication) with BA client backups to NAS systems . . .about +20tb of data also. So I'm also interested in any comments. I've been reading the vendor manuals, TSM doc's and Redbooks, this mailing list archive and anything else that Google finds. Here is what I think I've found out . . 2 ways to backup NAS: BA client on a CIFS share, and NDMP. NDMP: - uses full/incremental/differential backups - ndmp on netapp can be either file level or block/volume level - ndmp on celerra is only file level - file level ndmp backups are still file backups - lots of little files will STILL be a challenge! - a tsm ndmp pool cannot be migrated, reclaimed, movedata'ed - not sure about copy pools - it's the tsm management class that determines how long the backup is retained BA Client on a Share: - no journal backups (it's not a win filsystem!) - CIFS is slow - backups will take a long time - you do get to keep using your normal TSM mgt class policies - for netapp, there is a new snapdiff which provides journal like capabilities (saw some emails that this was very good!) The main point I've come away with is that switching to a NAS will not solve our backup problems . . .just change problems somewhat. I would appreciate any comments, additions, and especially CORRECTIONS. Thanks! Rick ADSM: Dist Stor Manager ADSM-L@VM.MARIST.EDU wrote on 06/23/2010 11:39:35 AM: We currently use traditional windows fileservers, but are being presented with an opportunity to start using a NAS device. I've been reading up on NDMP, doesn't sound to me like NAS is the backup admin's friend. Can anyone who has gone down this road share any of the biggest pros/cons/gotchas? I seem to recall from several years ago that getting the backup data offsite was an issue, but the NAS vendor claims this is no longer true. Currently using half a dozen fileservers to manage about 20TB of user data. Thanks, Steve Schaub Systems Engineer, Windows BlueCross BlueShield of Tennessee - Please see the following link for the BlueCross BlueShield of Tennessee E-mail disclaimer: http://www.bcbst.com/email_disclaimer.shtm - The information contained in this message is intended only for the personal and confidential use of the recipient(s) named above. If the reader of this message is not the intended recipient or an agent responsible for delivering it to the intended recipient, you are hereby notified that you have received this document in error and that any review, dissemination, distribution, or copying of this message is strictly prohibited. If you have received this communication in error, please notify us immediately, and delete the original message.
Re: NAS vs traditional fileservers
-TSM NDMP support will give you full or differentials only. No file level backups. You CAN do file-level restores. The nasty bit: however many versions of files you want to keep, you have to keep your NDMP fulls that far back. (Can you say buy stock in tape media companies and budget for a bigger library?) -Besides the excessive amount of media you need in order to keep multiple versions of 20TB full dumps, it will change the way you do restores. The only person who will have access to the restore capability is a TSM admin with SYSTEM level authority. That is very inconvenient for some of my customers, where the filesever admins can do their own restores by starting the TSM client from their console. -I have no vested interest, I don't sell hardware, but I would opt for the Netapp if possible because of the SNAPDIFF support. Why other vendors haven't provided that API I can't figure out. That is definitely the only true solution to the backup problem. -Whether you can create copy pools or not, depends on how you set up the TSM NDMP definitions. How you set up the TSM NDMP definitions depends on whether you have your tape drives direct-connected to the TSM server, or you plan to do your NDMP dumps over TCP/IP. Read Chap. 7 in the TSM admin guide on using NDMP. Read it again. About the 3rd time, it will start to make sense. -If you are going to NAS, remember to keep your LUNS a reasonable size; you don't want to have to scan a TB if you back up with CIFS, or dump a TB if you decide to do it with NDMP. -I think NDMP is just a bad idea all over, if you don't have SNAPDIFF. You have a backup product with the architecture and capability to a) back up only changed files, b) keep different files with different retention rules, and c) dedup on the client end with TSM 6.2. You give all that up and go back to something totally primitive with NDMP. -What I have done for some of my customers is go the CIFS route, but use multiple proxy servers. Have server A do its own backups, plus a PROXY backup for one of the NAS shares. Have server B do its own backups, plus a PROXY backup for another one of the NAS shares. Etc. So yes CIFS is slow, but if multiple servers each do a bit, it all gets done, which it won't if you have just 1 machine trying to scan a zillion tiny files on all those shares. And by using PROXYNODE, the backups all end up as filespaces belonging to 1 TSM node. That lets you move/change the PROXY servers as your load moves, and makes it easy to find things when restoring. -Original Message- From: ADSM: Dist Stor Manager [mailto:ads...@vm.marist.edu] On Behalf Of Richard Rhodes Sent: Wednesday, June 23, 2010 12:29 PM To: ADSM-L@VM.MARIST.EDU Subject: Re: [ADSM-L] NAS vs traditional fileservers We are in the same situation - possibly changing from Win Servers (using some kind of microsoft replication) with BA client backups to NAS systems . . .about +20tb of data also. So I'm also interested in any comments. I've been reading the vendor manuals, TSM doc's and Redbooks, this mailing list archive and anything else that Google finds. Here is what I think I've found out . . 2 ways to backup NAS: BA client on a CIFS share, and NDMP. NDMP: - uses full/incremental/differential backups - ndmp on netapp can be either file level or block/volume level - ndmp on celerra is only file level - file level ndmp backups are still file backups - lots of little files will STILL be a challenge! - a tsm ndmp pool cannot be migrated, reclaimed, movedata'ed - not sure about copy pools - it's the tsm management class that determines how long the backup is retained BA Client on a Share: - no journal backups (it's not a win filsystem!) - CIFS is slow - backups will take a long time - you do get to keep using your normal TSM mgt class policies - for netapp, there is a new snapdiff which provides journal like capabilities (saw some emails that this was very good!) The main point I've come away with is that switching to a NAS will not solve our backup problems . . .just change problems somewhat. I would appreciate any comments, additions, and especially CORRECTIONS. Thanks! Rick ADSM: Dist Stor Manager ADSM-L@VM.MARIST.EDU wrote on 06/23/2010 11:39:35 AM: We currently use traditional windows fileservers, but are being presented with an opportunity to start using a NAS device. I've been reading up on NDMP, doesn't sound to me like NAS is the backup admin's friend. Can anyone who has gone down this road share any of the biggest pros/cons/gotchas? I seem to recall from several years ago that getting the backup data offsite was an issue, but the NAS vendor claims this is no longer true. Currently using half a dozen fileservers to manage about 20TB of user data. Thanks, Steve Schaub Systems Engineer, Windows BlueCross BlueShield of Tennessee - Please see the following link for the BlueCross BlueShield
Re: NAS vs traditional fileservers
I am using NDMP on EMC Celera. I have done reclaim and movedata, but not migrate. Expires on NDMP runs very fast as it only looks at whole backups (full or differential). Instead of looking at hundreds of thousand little files, in expires the entire backup. -Original Message- From: ADSM: Dist Stor Manager [mailto:ads...@vm.marist.edu] On Behalf Of Richard Rhodes Sent: Wednesday, June 23, 2010 9:29 AM To: ADSM-L@VM.MARIST.EDU Subject: Re: NAS vs traditional fileservers We are in the same situation - possibly changing from Win Servers (using some kind of microsoft replication) with BA client backups to NAS systems . . .about +20tb of data also. So I'm also interested in any comments. I've been reading the vendor manuals, TSM doc's and Redbooks, this mailing list archive and anything else that Google finds. Here is what I think I've found out . . 2 ways to backup NAS: BA client on a CIFS share, and NDMP. NDMP: - uses full/incremental/differential backups - ndmp on netapp can be either file level or block/volume level - ndmp on celerra is only file level - file level ndmp backups are still file backups - lots of little files will STILL be a challenge! - a tsm ndmp pool cannot be migrated, reclaimed, movedata'ed - not sure about copy pools - it's the tsm management class that determines how long the backup is retained BA Client on a Share: - no journal backups (it's not a win filsystem!) - CIFS is slow - backups will take a long time - you do get to keep using your normal TSM mgt class policies - for netapp, there is a new snapdiff which provides journal like capabilities (saw some emails that this was very good!) The main point I've come away with is that switching to a NAS will not solve our backup problems . . .just change problems somewhat. I would appreciate any comments, additions, and especially CORRECTIONS. Thanks! Rick ADSM: Dist Stor Manager ADSM-L@VM.MARIST.EDU wrote on 06/23/2010 11:39:35 AM: We currently use traditional windows fileservers, but are being presented with an opportunity to start using a NAS device. I've been reading up on NDMP, doesn't sound to me like NAS is the backup admin's friend. Can anyone who has gone down this road share any of the biggest pros/cons/gotchas? I seem to recall from several years ago that getting the backup data offsite was an issue, but the NAS vendor claims this is no longer true. Currently using half a dozen fileservers to manage about 20TB of user data. Thanks, Steve Schaub Systems Engineer, Windows BlueCross BlueShield of Tennessee - Please see the following link for the BlueCross BlueShield of Tennessee E-mail disclaimer: http://www.bcbst.com/email_disclaimer.shtm - The information contained in this message is intended only for the personal and confidential use of the recipient(s) named above. If the reader of this message is not the intended recipient or an agent responsible for delivering it to the intended recipient, you are hereby notified that you have received this document in error and that any review, dissemination, distribution, or copying of this message is strictly prohibited. If you have received this communication in error, please notify us immediately, and delete the original message.
Re: NAS vs traditional fileservers
On Wed, Jun 23, 2010 at 11:51:14AM -0500, Prather, Wanda wrote: -I think NDMP is just a bad idea all over, if you don't have SNAPDIFF. You have a backup product with the architecture and capability to a) back up only changed files, b) keep different files with different retention rules, and c) dedup on the client end with TSM 6.2. You give all that up and go back to something totally primitive with NDMP. I would agree. Plus, NDMP just feels badly bolted onto the side of TSM. And we ran into this as well, while NDMP is a standard, everyone does is just differently enough that you get into that ball of headaches. We have a rather large client where we're having to do the proxy-run the BA client on a box that has the space NFS mounted dance because while whatever appliance they have does NDMP, it does it just differently enough that we couldn't get it to work with our current TSM setup. So, if you're thinking of NDMP you really need to try it first to make sure it actually works before committing to it. Like my collegue pointed out, we've been trying SNAPDIFF with some IBM re-branded NetApp boxes and seem to be having good luck with it so far. -- Thomas L. Kula | tk...@umich.edu | 734.764.6531 Information and Technology Services University of Michigan
Re: NAS vs traditional fileservers
We're in the middle of doing something similar. We have 17TB of windows file/print data being backed up by 5 servers, total of 33M files. Several of the volumes are almost 2TB with several million files and all of the problems associated with that. So the windows guy is moving all of this to CIFS and we'll (hopefully) end up with several smaller volumes. We did some testing using TSM 6.1.3.4 and NDMP full/diff to TS1120 tape. Backup times for 2 of the 3 test volumes was not that great, around 18MB/sec. The third volume backed up in half the time. According to the Netapp guy, some kind of contention/hotspot on the filer. This is backing up filer-server, not filer-tape. And filer-server allows you to do all of the traditional housekeeping tasks on the storage pools. Looked like it would be doable, until we added up all of the problems: 1. As mentioned elsewhere, the differentials, though just a fraction of the fulls estimate their size as the same as the fulls, so disk pools for the differentials were out, meaning all of the dozens of differentials every night would need a tape drive. A big scheduling headache, but not a show-stopper. 2. We tested TOC to get individual file restore capability. Performance was terrible; over an hour to restore one 50MB file. Only good news here is that increasing the size and number of files restored did not have an equivalent increase in restore time and the proposal was to keep enough snapshots to restore back two weeks. So the individual restore would be a last resort. 3. It appeared the tape compression on NDMP data was not nearly as good as on normal backups, leading to an increase in the number of tapes needed. 4. You will need a filer at your DR site to perform restores there. There was not enough upside to counteract the downsides for us, so we are going to use the SNAPDIFF feature for this application and use NDMP for a couple of big applications that were using image backups. NDMP ended up being over twice as fast for these. Sam Sheppard San Diego Data Processing Corp. (858)-581-9668 -Original Message- From: ADSM: Dist Stor Manager [mailto:ads...@vm.marist.edu] On Behalf Of Schaub, Steve Sent: Wednesday, June 23, 2010 8:40 AM To: ADSM-L@VM.MARIST.EDU Subject: [ADSM-L] NAS vs traditional fileservers We currently use traditional windows fileservers, but are being presented with an opportunity to start using a NAS device. I've been reading up on NDMP, doesn't sound to me like NAS is the backup admin's friend. Can anyone who has gone down this road share any of the biggest pros/cons/gotchas? I seem to recall from several years ago that getting the backup data offsite was an issue, but the NAS vendor claims this is no longer true. Currently using half a dozen fileservers to manage about 20TB of user data. Thanks, Steve Schaub Systems Engineer, Windows BlueCross BlueShield of Tennessee - Please see the following link for the BlueCross BlueShield of Tennessee E-mail disclaimer: http://www.bcbst.com/email_disclaimer.shtm
Re: NAS vs traditional fileservers
The NAS vendor is recommending that the NAS box both dedup and compress the files on it. This sounds good for space, but I'm thinking that this will cause NDMP backup to take even longer. I'm think if I do a NDMP full of +20tb of data and that data is all compressed, it's the same as uncompressing all that data to send it to TSM. ALso, the dedup would need to be un-deduped before sending it. Any thoughts on this? Rick Sheppard, Sam sshepp...@sddpc. ORG To Sent by: ADSM: ADSM-L@VM.MARIST.EDU Dist Stor cc Manager ads...@vm.marist Subject .EDU Re: NAS vs traditional fileservers 06/23/2010 01:04 PM Please respond to ADSM: Dist Stor Manager ads...@vm.marist .EDU We're in the middle of doing something similar. We have 17TB of windows file/print data being backed up by 5 servers, total of 33M files. Several of the volumes are almost 2TB with several million files and all of the problems associated with that. So the windows guy is moving all of this to CIFS and we'll (hopefully) end up with several smaller volumes. We did some testing using TSM 6.1.3.4 and NDMP full/diff to TS1120 tape. Backup times for 2 of the 3 test volumes was not that great, around 18MB/sec. The third volume backed up in half the time. According to the Netapp guy, some kind of contention/hotspot on the filer. This is backing up filer-server, not filer-tape. And filer-server allows you to do all of the traditional housekeeping tasks on the storage pools. Looked like it would be doable, until we added up all of the problems: 1. As mentioned elsewhere, the differentials, though just a fraction of the fulls estimate their size as the same as the fulls, so disk pools for the differentials were out, meaning all of the dozens of differentials every night would need a tape drive. A big scheduling headache, but not a show-stopper. 2. We tested TOC to get individual file restore capability. Performance was terrible; over an hour to restore one 50MB file. Only good news here is that increasing the size and number of files restored did not have an equivalent increase in restore time and the proposal was to keep enough snapshots to restore back two weeks. So the individual restore would be a last resort. 3. It appeared the tape compression on NDMP data was not nearly as good as on normal backups, leading to an increase in the number of tapes needed. 4. You will need a filer at your DR site to perform restores there. There was not enough upside to counteract the downsides for us, so we are going to use the SNAPDIFF feature for this application and use NDMP for a couple of big applications that were using image backups. NDMP ended up being over twice as fast for these. Sam Sheppard San Diego Data Processing Corp. (858)-581-9668 -Original Message- From: ADSM: Dist Stor Manager [mailto:ads...@vm.marist.edu] On Behalf Of Schaub, Steve Sent: Wednesday, June 23, 2010 8:40 AM To: ADSM-L@VM.MARIST.EDU Subject: [ADSM-L] NAS vs traditional fileservers We currently use traditional windows fileservers, but are being presented with an opportunity to start using a NAS device. I've been reading up on NDMP, doesn't sound to me like NAS is the backup admin's friend. Can anyone who has gone down this road share any of the biggest pros/cons/gotchas? I seem to recall from several years ago that getting the backup data offsite was an issue, but the NAS vendor claims this is no longer true. Currently using half a dozen fileservers to manage about 20TB of user data. Thanks, Steve Schaub Systems Engineer, Windows BlueCross BlueShield of Tennessee - Please see the following link for the BlueCross BlueShield of Tennessee E-mail disclaimer: http://www.bcbst.com/email_disclaimer.shtm - The information contained in this message is intended only for the personal and confidential use of the recipient(s) named above. If the reader of this message is not the intended recipient or an agent responsible for delivering it to the intended recipient, you are hereby notified that you have received this document in error and that any review, dissemination, distribution, or copying of this message is strictly prohibited. If you have received this communication in error, please notify us immediately, and delete the original message.
Re: NAS vs traditional fileservers
If you want to embarass a filer head with a bunch of SATA behind it (or the company that made it), give the filer head access to some fast tape drives and issue an NDMP backup. The filer will likely get very very busy. (People using the share will likely suffer slowness.) The good part about NDMP is that you can effectively offload the work to the data mover. The bad part is that once the files from many filerservers have been migrated to NAS, NDMP will sit and eat tapes like candy. Generating offsite copies use the data mover as well, and this can be a sizable CPU hit for the filer as well. If you teach the end users how to restore from snaps/checkpoints, you can make that part of it self-service, and hopefully get fewer restore requests as a result. As usual, YMMV. [RC] From: Richard Rhodes rrho...@firstenergycorp.com To: ADSM-L@VM.MARIST.EDU Date: 06/23/2010 11:11 AM Subject: Re: [ADSM-L] NAS vs traditional fileservers Sent by: ADSM: Dist Stor Manager ADSM-L@VM.MARIST.EDU The NAS vendor is recommending that the NAS box both dedup and compress the files on it. This sounds good for space, but I'm thinking that this will cause NDMP backup to take even longer. I'm think if I do a NDMP full of +20tb of data and that data is all compressed, it's the same as uncompressing all that data to send it to TSM. ALso, the dedup would need to be un-deduped before sending it. Any thoughts on this? Rick Sheppard, Sam sshepp...@sddpc. ORG To Sent by: ADSM: ADSM-L@VM.MARIST.EDU Dist Stor cc Manager ads...@vm.marist Subject .EDU Re: NAS vs traditional fileservers 06/23/2010 01:04 PM Please respond to ADSM: Dist Stor Manager ads...@vm.marist .EDU We're in the middle of doing something similar. We have 17TB of windows file/print data being backed up by 5 servers, total of 33M files. Several of the volumes are almost 2TB with several million files and all of the problems associated with that. So the windows guy is moving all of this to CIFS and we'll (hopefully) end up with several smaller volumes. We did some testing using TSM 6.1.3.4 and NDMP full/diff to TS1120 tape. Backup times for 2 of the 3 test volumes was not that great, around 18MB/sec. The third volume backed up in half the time. According to the Netapp guy, some kind of contention/hotspot on the filer. This is backing up filer-server, not filer-tape. And filer-server allows you to do all of the traditional housekeeping tasks on the storage pools. Looked like it would be doable, until we added up all of the problems: 1. As mentioned elsewhere, the differentials, though just a fraction of the fulls estimate their size as the same as the fulls, so disk pools for the differentials were out, meaning all of the dozens of differentials every night would need a tape drive. A big scheduling headache, but not a show-stopper. 2. We tested TOC to get individual file restore capability. Performance was terrible; over an hour to restore one 50MB file. Only good news here is that increasing the size and number of files restored did not have an equivalent increase in restore time and the proposal was to keep enough snapshots to restore back two weeks. So the individual restore would be a last resort. 3. It appeared the tape compression on NDMP data was not nearly as good as on normal backups, leading to an increase in the number of tapes needed. 4. You will need a filer at your DR site to perform restores there. There was not enough upside to counteract the downsides for us, so we are going to use the SNAPDIFF feature for this application and use NDMP for a couple of big applications that were using image backups. NDMP ended up being over twice as fast for these. Sam Sheppard San Diego Data Processing Corp. (858)-581-9668 -Original Message- From: ADSM: Dist Stor Manager [mailto:ads...@vm.marist.edu] On Behalf Of Schaub, Steve Sent: Wednesday, June 23, 2010 8:40 AM To: ADSM-L@VM.MARIST.EDU Subject: [ADSM-L] NAS vs traditional fileservers We currently use traditional windows fileservers, but are being presented with an opportunity to start using a NAS device. I've been reading up on NDMP, doesn't sound to me like NAS is the backup admin's friend. Can anyone who has gone down this road share any of the biggest pros/cons/gotchas? I seem to recall from several years ago that getting the backup data offsite was an issue, but the NAS vendor claims this is no longer true. Currently using half a dozen fileservers to manage about 20TB of user data. Thanks, Steve Schaub Systems Engineer, Windows BlueCross BlueShield of Tennessee
