Re: tapecycle and the doc
On Tue, 2005-03-15 at 23:52 +0100, Stefan G. Weichinger wrote: Hi, Tom, on Dienstag, 15. März 2005 at 23:32 you wrote to amanda-users: TS On Tue, 2005-03-15 at 10:25 -0700, Tom Schutter wrote: On Tue, 2005-03-15 at 01:03 -0500, Jon LaBadie wrote: While amanda is always willing to use a new tape in its rotation, it refuses to reuse a tape until at least 'tapecycle' number of other tapes have been used. TS Ooops. I think that should be: TS While amanda is always willing to use a new tape in its rotation, TS it refuses to reuse a tape until at least 'tapecycle-1' number of TS other tapes have been used. 10 points for that. In case you forgot, it does not appear to be fixed here yet: http://www.amanda.org/docs/amanda.8.html -- Tom Schutter (mailto:[EMAIL PROTECTED]) Platte River Associates, Inc. (http://www.platte.com)
Re: tapecycle and the doc
Hi, Tom, on Donnerstag, 17. März 2005 at 17:27 you wrote to amanda-users: TS In case you forgot, it does not appear to be fixed here yet: TS http://www.amanda.org/docs/amanda.8.html Thanks. Had fixed it in the source, but forgot to publish. It's html-only so far, the pdf doesn't get updated that often ... -- Stefan.
Re: tapecycle and the doc
Will Amanda use any tape that is more than tapecycle entries down the list or only the one of the bottom ? On Tue, Mar 15, 2005 at 11:52:01PM +0100, Stefan G. Weichinger wrote: Hi, Tom, on Dienstag, 15. März 2005 at 23:32 you wrote to amanda-users: TS On Tue, 2005-03-15 at 10:25 -0700, Tom Schutter wrote: On Tue, 2005-03-15 at 01:03 -0500, Jon LaBadie wrote: While amanda is always willing to use a new tape in its rotation, it refuses to reuse a tape until at least 'tapecycle' number of other tapes have been used. TS Ooops. I think that should be: TS While amanda is always willing to use a new tape in its rotation, TS it refuses to reuse a tape until at least 'tapecycle-1' number of TS other tapes have been used. 10 points for that. -- best regards, Stefan Stefan G. Weichinger mailto:[EMAIL PROTECTED] --- Brian R Cuttler [EMAIL PROTECTED] Computer Systems Support(v) 518 486-1697 Wadsworth Center(f) 518 473-6384 NYS Department of HealthHelp Desk 518 473-0773
Re: tapecycle and the doc
On Wed, Mar 16, 2005 at 08:27:51AM -0500, Brian Cuttler wrote: Will Amanda use any tape that is more than tapecycle entries down the list or only the one of the bottom ? On Tue, Mar 15, 2005 at 11:52:01PM +0100, Stefan G. Weichinger wrote: Hi, Tom, on Dienstag, 15. März 2005 at 23:32 you wrote to amanda-users: TS On Tue, 2005-03-15 at 10:25 -0700, Tom Schutter wrote: On Tue, 2005-03-15 at 01:03 -0500, Jon LaBadie wrote: While amanda is always willing to use a new tape in its rotation, it refuses to reuse a tape until at least 'tapecycle' number of other tapes have been used. TS Ooops. I think that should be: TS While amanda is always willing to use a new tape in its rotation, TS it refuses to reuse a tape until at least 'tapecycle-1' number of TS other tapes have been used. 10 points for that. -- best regards, Stefan Any, with the appropriate label, new or previously used, if not in the tapecycle-1 group. Hmm, as I write that, I'm not sure on a point. Suppose I have a tape with a proper label, but it does not appear in the tapelist file (perhaps due to hand editing or some other cosmic malady). Will amanda use that properly labeled, improperly listed tape? And maybe add it to the tapelist? -- Jon H. LaBadie [EMAIL PROTECTED] JG Computing 4455 Province Line Road(609) 252-0159 Princeton, NJ 08540-4322 (609) 683-7220 (fax)
Re: tapecycle and the doc
We have found that a shorter dumpcycle simplifies restores. We have also found that a shorter tape cycle simplified managerial issues... We need to investigate XYZ user please bring back all copies of their Lotus Notes mailbox. We find 20-25 tapes ample for most situations, gives a month plus restore period (we have dumps 5x/week) with a few of the older amanda configs on sight having a shorter period (we have intranet source for the external web server, we really only need to recover the OS and that is current at least once per designated dumpcycle). On Tue, Mar 15, 2005 at 01:03:31AM -0500, Jon LaBadie wrote: On Mon, Mar 14, 2005 at 09:14:43AM -0700, Tom Schutter wrote: I had some questions regarding tapecycle, and after reading the man page and the doc (old and new), I think that they fall short on describing what tapecycle should be set to. The minimum value of tapecycle is well covered, but not the maximum value, and how tapecycle should relate to the number of tapes that have been labeled. From the man page: tapecycle int Default: 15 tapes. The number of tapes in the Gee, I did not realize there was a default :) active tape cycle. This must be at least one larger than the number of Amanda runs done during a dump cycle (see the dumpcycle parameter) times the number of tapes used per run (see the runtapes parameter). For instance, if dumpcycle is set to 14 days, one Amanda run is done every day (Sunday through Satur- day), and runtapes is set to one, then tapecycle must be at least 15 (14 days * one run/day * one tape/run + one tape). In practice, there should be several extra tapes to allow for schedule adjustments or disaster recov- ery. So what is an active tape cycle? That is never defined anywhere. Bad wording. And it is seldom good practice to use a term (eg tapecycle) in the definition of the term. Although the last sentence is correct and it makes sense, it does not explain how tapecycle should relate to the actual number of labeled tapes. Here is my bad attempt at an improvement, please do not use it verbatim: You must have at least tapecycle tapes labeled, but you can have more. By labeling extra tapes, you can allow for schedule adjustments or disaster recovery. For example, lets say that your tapecycle is set to 20 and you have 20 labeled tapes. If you discover that tape #5 that you are about to put in the drive is bad, your only alternative is to immediately label a new replacement tape. If tapecycle was 20 and you had 25 labeled tapes, then you could put tape #6 in the drive and deal with the problem later. On the other hand, if the number of labeled tapes greatly exceeds tapecycle, then AMANDA (insert inefficiency issue here). Two things; I know of no inefficiency issues related to exceedingly large numbers of tapes in rotation. Or other problems, except cost, even in using fresh tapes every run. And as to your suggested revision, in writing man page documentation one must judge how much example, description, and definition should go into a document that is intended to be terse and quickly readable as reference, not how-to. Here is my attempt at a revision: tapecycle int Default: 15 tapes. Typically tapes are used by amanda in an ordered rotation. The tapecycle parameter defines the size of that rotation. The number of tapes in rotation must be larger than the number of tapes required for a complete dump cycle (see the dumpcycle parameter). This is calculated by multiplying the number of amdump runs per dump cycle (runspercycle parameter) times the number of tapes used per run (runtapes parameter). Typically two to four times this calculated number of tapes are in rotation. While amanda is always willing to use a new tape in its rotation, it refuses to reuse a tape until at least 'tapecycle' number of other tapes have been used. It is considered good administrative practice to set the tapecycle parameter slightly lower than the actual number of tapes in rotation. This allows the administrator to more easily cope with damaged or misplaced tapes or schedule adjustments that call for slight adjustments in the rotation order. -- Jon H. LaBadie [EMAIL PROTECTED] JG Computing 4455 Province Line Road(609) 252-0159 Princeton, NJ 08540-4322 (609) 683-7220 (fax) --- Brian R Cuttler [EMAIL PROTECTED] Computer Systems Support(v) 518 486-1697 Wadsworth Center(f) 518 473-6384 NYS Department of Health
Re: tapecycle and the doc
On Tue, 2005-03-15 at 01:03 -0500, Jon LaBadie wrote: On Mon, Mar 14, 2005 at 09:14:43AM -0700, Tom Schutter wrote: Here is my bad attempt at an improvement, please do not use it verbatim: Here is my attempt at a revision: tapecycle int Default: 15 tapes. Typically tapes are used by amanda in an ordered rotation. The tapecycle parameter defines the size of that rotation. The number of tapes in rotation must be larger than the number of tapes required for a complete dump cycle (see the dumpcycle parameter). This is calculated by multiplying the number of amdump runs per dump cycle (runspercycle parameter) times the number of tapes used per run (runtapes parameter). Typically two to four times this calculated number of tapes are in rotation. While amanda is always willing to use a new tape in its rotation, it refuses to reuse a tape until at least 'tapecycle' number of other tapes have been used. It is considered good administrative practice to set the tapecycle parameter slightly lower than the actual number of tapes in rotation. This allows the administrator to more easily cope with damaged or misplaced tapes or schedule adjustments that call for slight adjustments in the rotation order. Your attempt is far better than mine, and it says what I meant. -- Tom Schutter (mailto:[EMAIL PROTECTED]) Platte River Associates, Inc. (http://www.platte.com)
Re: tapecycle and the doc
On Tue, 2005-03-15 at 10:25 -0700, Tom Schutter wrote: On Tue, 2005-03-15 at 01:03 -0500, Jon LaBadie wrote: While amanda is always willing to use a new tape in its rotation, it refuses to reuse a tape until at least 'tapecycle' number of other tapes have been used. Ooops. I think that should be: While amanda is always willing to use a new tape in its rotation, it refuses to reuse a tape until at least 'tapecycle-1' number of other tapes have been used. -- Tom Schutter (mailto:[EMAIL PROTECTED]) Platte River Associates, Inc. (http://www.platte.com)
Re: tapecycle and the doc
Hi, Tom, on Dienstag, 15. März 2005 at 23:32 you wrote to amanda-users: TS On Tue, 2005-03-15 at 10:25 -0700, Tom Schutter wrote: On Tue, 2005-03-15 at 01:03 -0500, Jon LaBadie wrote: While amanda is always willing to use a new tape in its rotation, it refuses to reuse a tape until at least 'tapecycle' number of other tapes have been used. TS Ooops. I think that should be: TS While amanda is always willing to use a new tape in its rotation, TS it refuses to reuse a tape until at least 'tapecycle-1' number of TS other tapes have been used. 10 points for that. -- best regards, Stefan Stefan G. Weichinger mailto:[EMAIL PROTECTED]
tapecycle and the doc
I had some questions regarding tapecycle, and after reading the man page and the doc (old and new), I think that they fall short on describing what tapecycle should be set to. The minimum value of tapecycle is well covered, but not the maximum value, and how tapecycle should relate to the number of tapes that have been labeled. From the man page: tapecycle int Default: 15 tapes. The number of tapes in the active tape cycle. This must be at least one larger than the number of Amanda runs done during a dump cycle (see the dumpcycle parameter) times the number of tapes used per run (see the runtapes parameter). For instance, if dumpcycle is set to 14 days, one Amanda run is done every day (Sunday through Satur- day), and runtapes is set to one, then tapecycle must be at least 15 (14 days * one run/day * one tape/run + one tape). In practice, there should be several extra tapes to allow for schedule adjustments or disaster recov- ery. So what is an active tape cycle? That is never defined anywhere. Although the last sentence is correct and it makes sense, it does not explain how tapecycle should relate to the actual number of labeled tapes. Here is my bad attempt at an improvement, please do not use it verbatim: You must have at least tapecycle tapes labeled, but you can have more. By labeling extra tapes, you can allow for schedule adjustments or disaster recovery. For example, lets say that your tapecycle is set to 20 and you have 20 labeled tapes. If you discover that tape #5 that you are about to put in the drive is bad, your only alternative is to immediately label a new replacement tape. If tapecycle was 20 and you had 25 labeled tapes, then you could put tape #6 in the drive and deal with the problem later. On the other hand, if the number of labeled tapes greatly exceeds tapecycle, then AMANDA (insert inefficiency issue here). -- Tom Schutter (mailto:[EMAIL PROTECTED]) Platte River Associates, Inc. (http://www.platte.com)
Re: tapecycle and the doc
On Mon, Mar 14, 2005 at 09:14:43AM -0700, Tom Schutter wrote: I had some questions regarding tapecycle, and after reading the man page and the doc (old and new), I think that they fall short on describing what tapecycle should be set to. The minimum value of tapecycle is well covered, but not the maximum value, and how tapecycle should relate to the number of tapes that have been labeled. From the man page: tapecycle int Default: 15 tapes. The number of tapes in the Gee, I did not realize there was a default :) active tape cycle. This must be at least one larger than the number of Amanda runs done during a dump cycle (see the dumpcycle parameter) times the number of tapes used per run (see the runtapes parameter). For instance, if dumpcycle is set to 14 days, one Amanda run is done every day (Sunday through Satur- day), and runtapes is set to one, then tapecycle must be at least 15 (14 days * one run/day * one tape/run + one tape). In practice, there should be several extra tapes to allow for schedule adjustments or disaster recov- ery. So what is an active tape cycle? That is never defined anywhere. Bad wording. And it is seldom good practice to use a term (eg tapecycle) in the definition of the term. Although the last sentence is correct and it makes sense, it does not explain how tapecycle should relate to the actual number of labeled tapes. Here is my bad attempt at an improvement, please do not use it verbatim: You must have at least tapecycle tapes labeled, but you can have more. By labeling extra tapes, you can allow for schedule adjustments or disaster recovery. For example, lets say that your tapecycle is set to 20 and you have 20 labeled tapes. If you discover that tape #5 that you are about to put in the drive is bad, your only alternative is to immediately label a new replacement tape. If tapecycle was 20 and you had 25 labeled tapes, then you could put tape #6 in the drive and deal with the problem later. On the other hand, if the number of labeled tapes greatly exceeds tapecycle, then AMANDA (insert inefficiency issue here). Two things; I know of no inefficiency issues related to exceedingly large numbers of tapes in rotation. Or other problems, except cost, even in using fresh tapes every run. And as to your suggested revision, in writing man page documentation one must judge how much example, description, and definition should go into a document that is intended to be terse and quickly readable as reference, not how-to. Here is my attempt at a revision: tapecycle int Default: 15 tapes. Typically tapes are used by amanda in an ordered rotation. The tapecycle parameter defines the size of that rotation. The number of tapes in rotation must be larger than the number of tapes required for a complete dump cycle (see the dumpcycle parameter). This is calculated by multiplying the number of amdump runs per dump cycle (runspercycle parameter) times the number of tapes used per run (runtapes parameter). Typically two to four times this calculated number of tapes are in rotation. While amanda is always willing to use a new tape in its rotation, it refuses to reuse a tape until at least 'tapecycle' number of other tapes have been used. It is considered good administrative practice to set the tapecycle parameter slightly lower than the actual number of tapes in rotation. This allows the administrator to more easily cope with damaged or misplaced tapes or schedule adjustments that call for slight adjustments in the rotation order. -- Jon H. LaBadie [EMAIL PROTECTED] JG Computing 4455 Province Line Road(609) 252-0159 Princeton, NJ 08540-4322 (609) 683-7220 (fax)
