TSM Parallel restores question
Richard, HSM is the architecture that I need. Do you know a place in the documentation of TSM where it states that restores are done in parallel when using HSM? My suspicion is that restores are being done in parallel, but they all converge in the server and after that they are copied from the server in parallel to the destinations. I'm I right? Andres +-- |This was sent by andres...@gmail.com via Backup Central. |Forward SPAM to ab...@backupcentral.com. +--
Re: TSM Parallel restores question
On Mar 28, 2011, at 12:37 PM, andresms5 wrote: Richard, HSM is the architecture that I need. Do you know a place in the documentation of TSM where it states that restores are done in parallel when using HSM? My suspicion is that restores are being done in parallel, but they all converge in the server and after that they are copied from the server in parallel to the destinations. I'm I right? Hi, Andres - HSM does not involve restores: its terminology is recalls, where the whole approach is different as each client action requiring a file constitutes a separate request, as for example five people operating on their files in different areas of an HSM-controlled file system. Recalls can be performed intelligently and thus more efficiently where the client interacts with the server to order a batch such that tape mounts (where needed) are minimized, as can be achieved where the client is allowed to expand wildcards. And TSM will first bring back files it knows to be in the HSM disk storage pool, to go after tape-stored data after that. As the Unix HSM manual says: When you selectively recall a group of files, they are recalled in the most efficient, time-saving order based on where they are stored. Be aware that the convenience of HSM comes at a price: a great deal more complexity, and system overhead, with a variety of service daemons operating for and in the file system. Traversing the file system to find migration candidates is particularly expensive. Richard Sims
TSM Parallel restores question
I'm looking into methods for HSM for my company. One of the requirements I have is that restores must use the maximum speed we can achieve. I have looked at several TSM pages, but couldn't find something that explicitly explains how parallel restores (the NQR option) are going to be performed. My specific question is: Do all copies have to go over the server or can they go over different paths? For example: 2 files (F1,F2) are to be restored to two different primary systems (P1,P2) from 2 different secondary storage systems (S1,S2). Does TSM support a physical connection like the one shown bellow in a) or does it have to be a connection such as the one shown in b) a) P1 - F1 -- S1 P2 - F2 -- S2 b) P1 --F1---\/---F1 S1 - Server -- P2 --F2---/\---F2 S2 +-- |This was sent by andres...@gmail.com via Backup Central. |Forward SPAM to ab...@backupcentral.com. +--
Re: TSM Parallel restores question
HSM and backup-restore are very different concepts with equally different handling and, usually, architecture. While backup/restore is essentially serialized, HSM is on demand parallelized via independent processes. Define your objectives and then seek a storage architecture to fit the needs. Richard Sims On Mar 25, 2011, at 4:26 PM, andresms5 wrote: I'm looking into methods for HSM for my company. One of the requirements I have is that restores must use the maximum speed we can achieve. I have looked at several TSM pages, but couldn't find something that explicitly explains how parallel restores (the NQR option) are going to be performed. My specific question is: Do all copies have to go over the server or can they go over different paths? For example: 2 files (F1,F2) are to be restored to two different primary systems (P1,P2) from 2 different secondary storage systems (S1,S2). Does TSM support a physical connection like the one shown bellow in a) or does it have to be a connection such as the one shown in b) a) P1 - F1 -- S1 P2 - F2 -- S2 b) P1 --F1---\/---F1 S1 - Server -- P2 --F2---/\---F2 S2 +-- |This was sent by andres...@gmail.com via Backup Central. |Forward SPAM to ab...@backupcentral.com. +--
