256 device for Networker V7

[ns290114]

Hello, I'm joining the forum for the first time. I have two questions and a problem!! I need to configure more than 256 device on a datazone with a Networker server 7.1.2 and 40 Storage Nodes. Can you help me to understand if the 256 device limit applies to the whole datazone or to each jukebox, that is max device=256*no. jukeboxes? I have tried to configure two jukeboxes and now (I'm testing the solution) I have more than 256 devices without any problem. Second question: disk device, such as AFTD, must be "counted" in the 256 devices or 256 devices is only for tape device?
Thanks for any answers.

 

[605]

The number of devices applies to the whole data zone.

An (A)FTD is also treated as any other device because it uses the same mechanism.

 

[tremblyj]

Hi,

Your limit is 256 simultaneous data streams per cluster and 32 simultaneous data streams per node (server, storage node). The setting is called parallelism. It's multiplexing various data sources (C:, D:, System Data, Repair Disk, etc) from multiple clients to one or more storage devices.

Each device's simultaneous data stream limit (max 32)depends on it's speed and the power of it's host and the speed of it's network adapter and the network it's attached to. For example, I have a library with dual SDLT320's attached to one IBM pizzabox with dual Pentium4 XEONs and a 1GB/s network adapter.

Because my Networker server has the power to handle it, I set the server's parallelism to the max (32) and because the Ulta160 SCSI interface that I use with my library allows the drives to run at their max speed of 16MB/s (32MB/s with 2:1 compression), the library's parallelism is also set to the server's max (32) and I set each of the two devices' parallelism settings to 16 each.

The parallelism on most of my clients is set to 6 but if it's a smaller box with IDE drives, I set it to 4 on them. I get between 16MB/s and 32MB/s throughput on each SDLT320 (average is 22MB/s). The rate will jump around during the backup depending on what kind of files are being backed up at the time.

I do full backups on 50 servers every night and I get 817GB backed up to 5 tapes in 10.5 hours. We have a new library with dual LTO2 400GB drives that will smoke the one I'm currently using. It will be able to backup the same data to two LTO2 tapes in 2 hours!

I've never heard of a device limit. I believe that the limit on the number of devices in a cluster and the number of slots in a library depend solely on your licensing and the size of your budget.




John Trembly
mailto:John.Trembly@dpcdsb.org

 

[605]

The limitation of ACTIVE devices and streams is actually limited by the license type and the nuber of Storage Node
licenses. It is as follows:

NetWorke Edition Drives Streams
Server 16 32
each Storage Node +16 +32


Power Edition Drives Streams
Server 32 64
each Storage Node +32 +64