Upgrading to NeteBackup DataCenter

[BillT31]

I am going to be upgrading from CA Arcserve 2000 to NetBackup DataCenter and would like some feed back on performance increases from someone who has a similar environment.

Our current environment consists of about 40 NT/2000 server containing about 500 GB of data. We also have a 75 GB Exchange 5.5 database as well as 6 SQL server. The backup server is connected to the LAN at 1 GB and all other server are 100 MB.

We will be going from Arcserve using a 2 drive LTO library to NetBackup using a 4 drive LTO2 library.

A full system backup this weekend took 24 hrs. to complete using a single drive for all data servers. The other drive is used for Exchange & SQL databases.

How much time can I expect to cut off the backups using multiple drives as well as the Mulitplexing feature in NetBackup.

Thanks,
Bill

 

[PGPhantom]

Really tough question. It depends on so much, including the configuration of your network. What are the current KB/sec total of Arcserve?

Typically in NetBackup you should get around 15,000 - 20,000 KB/sec with LTO gen 2 drives as long as everything is configured correctly. I have seen upwards of 50Gb/hour per drive.

 

[BillT31]

My entire full backup last weekend of 527 GB averaged about 6,400 KB/sec. My largest file server which has about 160 GB of data averaged about 10,000 KB/sec.

Assuming I average the same speed with NetBackup, roughly how many servers can be backed up at the same time using multiplexing? My backup server is connected at 1 GB & all other servers are connected at 100 MB. Can I expect to cut the time in half if I stream 2 servers concurrently? What have you found to be the most efficent number of data streams? We will be purchasing a new server for NBU so any recommendations on processor & memory are welcomed.

 

[PGPhantom]

6,400 KB/sec is rather slow for LTO gen2 - If you had mentioned the speed and not the drive type I would of assumed you had DLT7000/8000 drives as that is the speed typically seen on those types of drivees.

There is a lot of discussion around what is an ideal server for an NBU master server. What we have, after a lot of investigation - A Dell PowerEdge 2650. It has dual Xeon 2.3GHz CPU's (Xeon as W2K sees then as quad CPU's due to streaming - A big performance boost), 4GB RAM, 120GB Disk Space and if your switch supports it, a GB Ethernet card. I say if your switch supports it because if you have a GB car set for auto and a switch that does not support GB then you will actually get less than 100Mb/sec.

On the other servers, the cards all HAVE to be configured for 100/Full, Checksum offloading on for TX/RX, and Flow control on for TX/RX - Once again - The switch must coincide with the settings - With the GB - The card must be auto and the switch must be auto but if flow control and checksum offloading are not on for TX/Rx then you will get a performance hit. Another thing - NEVER, NEVER, EVER connect tape drives to the master server.

I know some may diagree with this but when we had NBU 3.4.1 we had a drive conected to the master and we would often get errors 52, 54 which are network timeouts - The server gets too busy and data gets lost - Just trust me on this one as we did a lot of packet capturing to verify this.

As for multiplexing - Only ever multiplex incremental backups - In NBU you can determine different schedules for full and incremental backups - For Full backups I never use multiplexing and on incrementals they vary between 2-4 clients - Reason, on incremental backups the server is constantly searching for archive bits that have been set so you get a lot of lag time between data packets - This is where multiplexing comes in. If you have servers that are used a lot, I decrease to 2, if they are used infrequently, I increase to 4.

 

[BillT31]

Thanks for the reply.

6,400 KB/sec is the average of my entire backup job. Some older servers back up at a slower speed. Most of my servers (Dell 2650's) average about 10,000 KB/sec. This is using an LTO gen 1 Library. I will be getting a gen 2 4 drive Library along with NBU.

As far as the NBU server, our standard server here is a Dell 2650 w/Xeon Processor and I had planned on getting duel processors but our vender never said anything about splitting up the Master & Media servers. I'll have to ask him about it.

Our current backup server is the only server current connect at 1GB. All the other servers were configured for 100/Full on both the server & the switch but the Checksome & Flow Control were left at the default settings. I'll have to test these settings.

Management wants to know how much we will gain in performance upgrading from Arcserve 2000 with a 2 drive Library to NBU with a 4 drive library. I've asked my vender to supply a few references of similar size companies who use NBU but so far haven't gotten any, so I appreciate the responses.