Description

• take an HP rx7620 (max. 8 CPUs, 16-32GB of RAM, 15 PCI-X slots, 8GByte/s I/O bandwidth)
• add one 10Gb NIC --> 800-900MByte/s network I/O
• add up to 14 Dual-Port FC cards --> 28 FC ports
• connect 6 tape drives (for 100MB/s I/O rate per unit)
• leaves 22 ports for FC disks

Reasoning

This solution is a "high-end" implementation of the LocalCacheForTapeServers idea for tape units which can run at ~100MB/s (even with the FileMarks limitations). It provides sufficient I/O capabilities to run a larger number of tape units at their maximum speed in order to increase (tape-)efficiency as much as possible. In addition it opens a simply way of upgrading to even faster tape units while keeping the high efficiency...without changes to the infratructure (network etc.).

The disk pools could be run in an even more flexible way as for the MidTapeServer solution.

The main disadvantage of this solution is the need for 10Gb network connectivity. But if the tape units are capable of more than 100MB/s (including all limitiations) the network would become the bottleneck if the tape server is connected with 1Gb only.

Software

This box would run any standard Linux (SLC3 - SLC21) with a 2.6 kernel. I/O prioritization is also possible, but might not be necessary. As for any other idea involving LocalCacheForTapeServers, CASTOR has to be changed...

-- AndreasHirstius - 03 May 2005