Re: Ecrix VXA 33/66 tapes with Retrospect
After I saw the series of postings on VXA tape capacity, I thought it would help to get some info to you straight from us at Ecrix. In this email, you'll find answers to these questions: - Which files compress and which don't? - How does Dantz software compression work with VXA? - How does a VXA drive optimize for speed vs. capacity? - What are the factory settings of the VXA drive? - Does the firmware level affect tape capacity? - How do I check my firmware version? - How is tape capacity reported? - How do I check my firmware version? - Where do I get VXAtool and new VXA Firmware? - Does VXAtool run on Mac? - Does the VXA drive use streaming like other tape drives? I hope that this is useful info. Let me know if you have any more questions or comments. - Frank Saab [EMAIL PROTECTED] Ecrix -- - Which files compress and which don't? gif files, jpeg's, mpeg's, mp3's, etc. are pre-compressed and you cannot expect any further compression. Text files, word documents, source code, etc., compress at an average ratio of 2 to 1. Binaries, executables, and system files compress at about 1.4 to 1. - How does Dantz software compression work with VXA? If your files are compressible, turn software compression off and hardware compression on. If the files are not compressible, turn both hardware and software compression OFF. You reset hardware compression with VXAtool. Software compression is set in the Retrospect interface. If you are having trouble setting hardware/software compression, please contact us at [EMAIL PROTECTED] - How does a VXA drive optimize for speed vs. capacity? The VXA drive can run in one of two modes: One optimizes for speed (this is the factory setting). The other mode optimizes for capacity. If your connection to the drive is slow, use the capcity mode to get the most capacity on the tape. You can reset the mode with VXAtool. - What are the factory settings of the VXA drive? The drive is set with hardware compression on and is set to favor speed over capacity. - Does the firmware level affect tape capacity? VXA firmware older than V21E1E1F (released 04/04/00) does not let you select speed versus capacity optimization. With the newer firmware, you can use VXAtool to reset this option. The latest version of firmware is V2959 released 02/26/01. - How do I check my firmware version? You can use VXAtool to check your firmware version. - How is tape capacity reported? Almost all storage hardware manufacturers (including Ecrix) use the IEEE method of reporting capacity, where one GB is 1000 x 1000 x 1000 bytes. Retrospect software uses a different method, where one GB is 1024 x 1024 x 1024 bytes. Because of this, the maximum capacity that Retrospect will report on a VXA 33 GB tape is just over 30 GB, which is almost 33 GB by the IEEE method. - Where do I get VXAtool and new VXA Firmware? They are available from http://vxa.com/support - Does VXAtool run on Mac? VXAtool is available in different versions for Mac, Linux, Windows, and DOS. - Does the VXA drive use streaming like other tape drives? VXA drive is the first tape drive that does not use streaming. Its packet format lets it work at variable speed. This avoids shoeshining/backhitching, which are detrimental to the drive and to the tape. We have videos explaining this in more detail at http://vxa.com/vxa and http://vxa.com/tour I hope that this is useful info. Let me know if you have any more questions or comments. - Frank Saab [EMAIL PROTECTED] Ecrix
Ecrix VXA 33/66 tapes with Retrospect
Hi Backup People, I have set up one of my clients with an Ecrix VXA tape drive using the above media. It was my understanding that with the hardware compression built into the drive turned on I would get the full 66 Gig capacity. My client has just rung me to say that Retrospect is requesting a new tape a quick inspection (over the phone via my client) of the original tape in the scheduled backup set revealed that it has used 33 Gig. I will have to go investigate this but could someone who knows please tell me if I need to have software compression turned on to get 66 Gig out of the tape or is there something else making Retrospect ask for another tape. The backup set which was due to be used tonight was set A Retrospect is saying that it will call the new tape 2-set A which makes me think it probably is full. Thanks in advance to anyone who takes the time to reply Regards -- Rob Findlay Mactherapy - Solutions Support For Macintosh Computers http://www.mactherapy.com * -- -- To subscribe:[EMAIL PROTECTED] To unsubscribe: [EMAIL PROTECTED] Archives:http://list.working-dogs.com/lists/retro-talk/ Search: http://www.mail-archive.com/retro-talk%40latchkey.com/ For urgent issues, please contact Dantz technical support directly at [EMAIL PROTECTED] or 925.253.3050.
Re: Ecrix VXA 33/66 tapes with Retrospect
on 3/1/01 6:59 AM, Douglas K Wyman at [EMAIL PROTECTED] wrote: I have set up one of my clients with an Ecrix VXA tape drive using the above media. It was my understanding that with the hardware compression built into the drive turned on I would get the full 66 Gig capacity. My client has just rung me to say that Retrospect is requesting a new tape a quick inspection (over the phone via my client) of the original tape in the scheduled backup set revealed that it has used 33 Gig. I will have to go investigate this but could someone who knows please tell me if I need to have software compression turned on to get 66 Gig out of the tape or is there something else making Retrospect ask for another tape. 66gig is the maximum at optimum performance. IE: backing up word files on a local drive. I have the latest firmware in my drive and while it helped I still only get about 34-38 gig per tape. My setup is a dedicated machine running over a switched 100baseT network backing up mainly graphics files. I get 180meg/min. I am very happy with this as graphics files are very compressible (sp?). Garret --- Garret J. Cleversley | Vice President | Apple Product Professional CPI Digital Services, Inc. | Center Page, Inc. | 716-822-2212 Certified Apple Technician | Apple Solution Experts, Consultant A+ Network+ Certified, Member - CompTIA IT Professionals --- -- -- To subscribe:[EMAIL PROTECTED] To unsubscribe: [EMAIL PROTECTED] Archives:http://list.working-dogs.com/lists/retro-talk/ Search: http://www.mail-archive.com/retro-talk%40latchkey.com/ For urgent issues, please contact Dantz technical support directly at [EMAIL PROTECTED] or 925.253.3050.
Re: Ecrix VXA 33/66 tapes with Retrospect
Retrospect will detect that the drive has compression and will override the software settings, so having software compression enabled should not affect performance if you are running Retrospect 4.3 with Ecrix's latest firmware. Regards, Irena Solomon Dantz Technical Support 925.253.3050 From: Rob Findlay [EMAIL PROTECTED] Subject: Re: Ecrix VXA 33/66 tapes with Retrospect That's what I wanted to know Thanks Garret. Thanks also to Douglas who suggested I upgrade the firmware. Does anyone use software compression or is this a waste of time? I'm sure it slows things down even more. -- Rob Findlay Mactherapy - Solutions Support For Macintosh Computers http://www.mactherapy.com * From: "Garret J. Cleversley" [EMAIL PROTECTED] Reply-To: "retro-talk" [EMAIL PROTECTED] Date: Thu, 01 Mar 2001 11:04:19 -0500 To: retrospect [EMAIL PROTECTED] Subject: Re: Ecrix VXA 33/66 tapes with Retrospect on 3/1/01 6:59 AM, Douglas K Wyman at [EMAIL PROTECTED] wrote: I have set up one of my clients with an Ecrix VXA tape drive using the above media. It was my understanding that with the hardware compression built into the drive turned on I would get the full 66 Gig capacity. My client has just rung me to say that Retrospect is requesting a new tape a quick inspection (over the phone via my client) of the original tape in the scheduled backup set revealed that it has used 33 Gig. I will have to go investigate this but could someone who knows please tell me if I need to have software compression turned on to get 66 Gig out of the tape or is there something else making Retrospect ask for another tape. 66gig is the maximum at optimum performance. IE: backing up word files on a local drive. I have the latest firmware in my drive and while it helped I still only get about 34-38 gig per tape. My setup is a dedicated machine running over a switched 100baseT network backing up mainly graphics files. I get 180meg/min. I am very happy with this as graphics files are very compressible (sp?). Garret -- -- To subscribe:[EMAIL PROTECTED] To unsubscribe: [EMAIL PROTECTED] Archives:http://list.working-dogs.com/lists/retro-talk/ Search: http://www.mail-archive.com/retro-talk%40latchkey.com/ For urgent issues, please contact Dantz technical support directly at [EMAIL PROTECTED] or 925.253.3050.
Re: Ecrix VXA 33/66 tapes with Retrospect
That's what I wanted to know Thanks Garret. Thanks also to Douglas who suggested I upgrade the firmware. Does anyone use software compression or is this a waste of time? I'm sure it slows things down even more. -- Rob Findlay Mactherapy - Solutions Support For Macintosh Computers http://www.mactherapy.com * From: "Garret J. Cleversley" [EMAIL PROTECTED] Reply-To: "retro-talk" [EMAIL PROTECTED] Date: Thu, 01 Mar 2001 11:04:19 -0500 To: retrospect [EMAIL PROTECTED] Subject: Re: Ecrix VXA 33/66 tapes with Retrospect on 3/1/01 6:59 AM, Douglas K Wyman at [EMAIL PROTECTED] wrote: I have set up one of my clients with an Ecrix VXA tape drive using the above media. It was my understanding that with the hardware compression built into the drive turned on I would get the full 66 Gig capacity. My client has just rung me to say that Retrospect is requesting a new tape a quick inspection (over the phone via my client) of the original tape in the scheduled backup set revealed that it has used 33 Gig. I will have to go investigate this but could someone who knows please tell me if I need to have software compression turned on to get 66 Gig out of the tape or is there something else making Retrospect ask for another tape. 66gig is the maximum at optimum performance. IE: backing up word files on a local drive. I have the latest firmware in my drive and while it helped I still only get about 34-38 gig per tape. My setup is a dedicated machine running over a switched 100baseT network backing up mainly graphics files. I get 180meg/min. I am very happy with this as graphics files are very compressible (sp?). Garret --- Garret J. Cleversley | Vice President | Apple Product Professional CPI Digital Services, Inc. | Center Page, Inc. | 716-822-2212 Certified Apple Technician | Apple Solution Experts, Consultant A+ Network+ Certified, Member - CompTIA IT Professionals --- -- -- To subscribe:[EMAIL PROTECTED] To unsubscribe: [EMAIL PROTECTED] Archives:http://list.working-dogs.com/lists/retro-talk/ Search: http://www.mail-archive.com/retro-talk%40latchkey.com/ For urgent issues, please contact Dantz technical support directly at [EMAIL PROTECTED] or 925.253.3050. -- -- To subscribe:[EMAIL PROTECTED] To unsubscribe: [EMAIL PROTECTED] Archives:http://list.working-dogs.com/lists/retro-talk/ Search: http://www.mail-archive.com/retro-talk%40latchkey.com/ For urgent issues, please contact Dantz technical support directly at [EMAIL PROTECTED] or 925.253.3050.
Re: Ecrix VXA 33/66 tapes with Retrospect
on 3/1/01 11:28 AM, Rob Findlay at [EMAIL PROTECTED] wrote: Does anyone use software compression or is this a waste of time? I'm sure it slows things down even more. It slows it down and is unneeded as hardware compression is built in. Garret --- Garret J. Cleversley | Vice President | Apple Product Professional CPI Digital Services, Inc. | Center Page, Inc. | 716-822-2212 Certified Apple Technician | Apple Solution Experts, Consultant A+ Network+ Certified, Member - CompTIA IT Professionals --- -- -- To subscribe:[EMAIL PROTECTED] To unsubscribe: [EMAIL PROTECTED] Archives:http://list.working-dogs.com/lists/retro-talk/ Search: http://www.mail-archive.com/retro-talk%40latchkey.com/ For urgent issues, please contact Dantz technical support directly at [EMAIL PROTECTED] or 925.253.3050.
Re: Ecrix VXA 33/66 tapes with Retrospect
on 3/1/01 8:04 AM, "Garret J. Cleversley" [EMAIL PROTECTED] wrote: I am very happy with this as graphics files are very compressible (sp?). Garret Eh? It really depends on the type of file you are compressing. If the image (or any data for that matter) is already stored in a compressed format (for example, .gif images are stored compressed), then there is absolutely no gain and in fact, you might have a negative effect. For example, a quick and dirty test: I have a .gif file on disk that is: 12,461 bytes Compressed with Stuffit, the image becomes: 12,677 bytes It is actually LARGER in compressed format! Just wanted to clarify that statement lest anyone become enamored with the idea that all graphic files compress well. thanks, -jon -- -- To subscribe:[EMAIL PROTECTED] To unsubscribe: [EMAIL PROTECTED] Archives:http://list.working-dogs.com/lists/retro-talk/ Search: http://www.mail-archive.com/retro-talk%40latchkey.com/ For urgent issues, please contact Dantz technical support directly at [EMAIL PROTECTED] or 925.253.3050.
RE: Ecrix VXA 33/66 tapes with Retrospect
You do run the risk of expanding your data if you back it up with compression... but that depends on the drive technology. For example, the AIT algo for compression checks to see if the data is compressible before writing it. If the data is compressible, it writes a compressed block. If the data is not compressible (.gif, .jpg, etc), then it writes an uncompressed block. It's able to do that on-the-fly and still meet the rated transfer speed. By using this method, you do not run the risk of expanding your data when it is pre-compressed. That's why I encourage all of our AIT customers to keep hardware compression activated. With other technologies that we distribute, I advise that they turn compression off when dealing with non-linear video, audio or pre-compressed graphics, otherwise they will not store the full capacity. Steve www.cybernetics.com [EMAIL PROTECTED] -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Daniel O'Donnell Sent: Thursday, March 01, 2001 2:12 PM To: retro-talk Subject: Re: Ecrix VXA 33/66 tapes with Retrospect I was puzzled by the statement as well. The biggest files these days tend to be motion graphics or animations such as QuickTime or MPEG. QT and MPEG are already compressed and will show very little if any subsequent compression. At 10:23 AM -0800 on 3/1/01, Jon Stevens wrote: on 3/1/01 8:04 AM, "Garret J. Cleversley" [EMAIL PROTECTED] wrote: I am very happy with this as graphics files are very compressible (sp?). Garret Eh? It really depends on the type of file you are compressing. If the image (or any data for that matter) is already stored in a compressed format (for example, .gif images are stored compressed), then there is absolutely no gain and in fact, you might have a negative effect. For example, a quick and dirty test: I have a .gif file on disk that is: 12,461 bytes Compressed with Stuffit, the image becomes: 12,677 bytes It is actually LARGER in compressed format! Just wanted to clarify that statement lest anyone become enamored with the idea that all graphic files compress well. thanks, -jon -- -- To subscribe:[EMAIL PROTECTED] To unsubscribe: [EMAIL PROTECTED] Archives:http://list.working-dogs.com/lists/retro-talk/ Search: http://www.mail-archive.com/retro-talk%40latchkey.com/ For urgent issues, please contact Dantz technical support directly at [EMAIL PROTECTED] or 925.253.3050. -- -- To subscribe:[EMAIL PROTECTED] To unsubscribe: [EMAIL PROTECTED] Archives:http://list.working-dogs.com/lists/retro-talk/ Search: http://www.mail-archive.com/retro-talk%40latchkey.com/ For urgent issues, please contact Dantz technical support directly at [EMAIL PROTECTED] or 925.253.3050.
Re: Ecrix VXA 33/66 tapes with Retrospect
At 18:48 +0800 3/1/01, Rob Findlay wrote: Hi Backup People, I have set up one of my clients with an Ecrix VXA tape drive using the above media. It was my understanding that with the hardware compression built into the drive turned on I would get the full 66 Gig capacity. My client has just rung me to say that Retrospect is requesting a new tape a quick inspection (over the phone via my client) of the original tape in the scheduled backup set revealed that it has used 33 Gig. I will have to go investigate this but could someone who knows please tell me if I need to have software compression turned on to get 66 Gig out of the tape or is there something else making Retrospect ask for another tape. For maximum capacity... 1. make sure VXA drive has the latest firmware 2. make sure VXA drive has hardware compression turned on 3. make sure VXA drive favors capacity over speed There are 2 settings, when configuring the VXA drive, that that affect tape capacity... capacity [ device] [capacity] [y or n] set_compression [ device] [set_compression] [y or n] I believe that the factory defaults are: set_compression y capacity n At 11:42 -0600 3/1/01, Douglas K Wyman wrote: Streaming tape drives (virtually all modern drives including Exabyte, DDS-DAT, AIT, VXA, DLT, LTO etc) have a real-time requirement for data flow. If the backups system is not able to keep the tape drive buffer above its low water mark, the drive will start writing extended record gaps (tape with no user data; the lexicon and semantics vary from vendor to vendor) in order to avoid stopping the tape motion while waiting for data. Obviously this consumes more tape than if all data records were written contiguously without record gaps. Doug, My understanding is that the VXA drive does packet writes and has a variable speed writing mechanism and thus has much less of a problem with inter-record gaps (gaps of about 100k per pause with capacity turned on with about a 10% loss in speed) (I'll Bcc: Ecrix tech support on this just in case I have the info wrong.) -- -- [EMAIL PROTECTED] Ben Liberman -- -- -- To subscribe:[EMAIL PROTECTED] To unsubscribe: [EMAIL PROTECTED] Archives:http://list.working-dogs.com/lists/retro-talk/ Search: http://www.mail-archive.com/retro-talk%40latchkey.com/ For urgent issues, please contact Dantz technical support directly at [EMAIL PROTECTED] or 925.253.3050.
Re: Ecrix VXA 33/66 tapes with Retrospect
At 1:41 PM -0600 3/1/01, Ben Liberman wrote: 1. make sure VXA drive has the latest firmware 2. make sure VXA drive has hardware compression turned on 3. make sure VXA drive favors capacity over speed There are 2 settings, when configuring the VXA drive, that that affect tape capacity... capacity [ device] [capacity] [y or n] set_compression [ device] [set_compression] [y or n] I believe that the factory defaults are: set_compression y capacity n My understanding is that the VXA drive does packet writes and has a variable speed writing mechanism and thus has much less of a problem with inter-record gaps (gaps of about 100k per pause with capacity turned on with about a 10% loss in speed) Ben, I agree that Ecrix is the company most visibly in touch with this problem. The principals of the company came from Exabyte and learned from the experience. The VXA drives do a great deal to compensate for data starvation, particularly considering the low price point of the product. Setting the VXA drive parameter to favour capacity, however, will still increase the number of shoe-shines due to data starvation and therefore increase the backup time. You make your choices and take your chances, as they say. Good comments, taken in context! Doug.Wyman Houston TX -- -- To subscribe:[EMAIL PROTECTED] To unsubscribe: [EMAIL PROTECTED] Archives:http://list.working-dogs.com/lists/retro-talk/ Search: http://www.mail-archive.com/retro-talk%40latchkey.com/ For urgent issues, please contact Dantz technical support directly at [EMAIL PROTECTED] or 925.253.3050.
