Dmitri, To answer your questions:
Q: Why is Gresham's EDT product required as part of the Storage Agent/LAN-Free solution? A: Gresham's EDT product was selected to handle tape resource brokering between TSM and ACSLS/LibStation. In particular, EDT-DistribuTAPE enables TSM to use a single scratch pool between multiple TSM servers. EDT-DistribuTAPE ensures that when multiple TSM servers use a single scratch pool, tapes that are in use by one TSM server are not allocated to other TSM servers ensuring that data integrity is maintained and data is protected on each volume. Q: What are the issues involved with sharing ACSLS between multiple TSM servers? A: If you do not use EDT-DistribuTAPE in a solution where you have multiple TSM servers accessing a single ACSLS server, the largest problem that you will face is the fact that TSM is designed to employ ACSLS scratch pool 0. Since multiple TSM servers would be accessing the same tape pool, you cannot ensure that a volume that is in use by one TSM server will not be assigned and overwritten by another TSM server. Q: What is EDT's exact role in LAN-Free data transfer? A: EDT-DistribuTAPE is responsible for satisfying mount requests, ensuring that the proper tape volume has been mounted, that the volume is properly prepared for use and that the data path has been properly established. Once this process has been completed, EDT-DistribuTAPE turns control over to TSM along with all appropriate information allowing TSM to perform the backup. EDT-DistribuTAPE does not actively participate on the data path. Q: Has anyone setup an ACSLS library for SAN using EDT? A: Gresham has numerous clients who use EDT-DistribuTAPE with ACSLS/LibStation and TSM in a SAN environment. Lately, Gresham has deployed LAN-Free solutions at several locations all with great success. For additional information, please refer to www.gresham-software.com/tivoli. Christopher S. Young Senior System Engineer Gresham Enterprise Storage www.greshamstorage.com Office: 303.413.1799 x 205 Mobile: 303.717.2745 -----Original Message----- From: Dmitri Pasyutin [mailto:[EMAIL PROTECTED]] Sent: Monday, October 29, 2001 1:58 PM To: [EMAIL PROTECTED] Subject: ACSLS, library sharing and SAN Hi fellow TSMers, I use an ACSLS (STK 9360) library with my TSM server (4.2.1 on AIX). It had been great news for me to hear that as of v4.2.0 TSM supports ACSLS library sharing, and now SAN data transfer with ACSLS as of v4.2.1. Still, after thinking about it many times, I still can't figure out why this came so late. Sharing of SCSI STK libraries has been supported as of v3.7, but not ACSLS. However, with its (100%-software) ACSSI interface, TSM controls an ACSLS robot just as it would a SCSI one. There seems to be no technical reason why an ACSLS robot could not be shared between multiple servers, i.e. I can't see how it can be related to hardware or the physical device driver. And even now with SAN support, a third-party product like Gresham's EDT is required as the interface between the library and the storage agent. Why? Can someone enlighten me on the ACSLS sharing issue? What is EDT's exact role in lan-free data transfer? Also, if someone has set up an ACSLS library for SAN using EDT, I would very much like to hear about your experiences. Thanks in advance. Yours truly, -- Dmitri PASYUTIN TSM administrator Paris, France
