https://community.hpe.com/t5/storeever-tape-storage/problems-with-hardware-compression-c1537a-dds3/m-p/2767774#M4173 Hello,<BR /><BR />How did you set the switches 1 and 2 (controlling compression)?<BR /><BR />Switch 1 should be set to 1 to enable compression. Switch 2 should be set to 1 as well for Host control.<BR /><BR />HTH,<BR />Vince Fri, 19 Jul 2002 11:38:50 GMT Vincent Farrugia 2002-07-19T11:38:50Z https://community.hpe.com/t5/storeever-tape-storage/problems-with-hardware-compression-c1537a-dds3/m-p/2767773#M4172 Hi,<BR /><BR />i??ve got a problem with hardware compression on my C1537A.<BR />Hardware Compression oin the drive is enabled but the drive??s storing max. 11GB on my DDS3 Tape with a max write rate of 60mb/min. Why is the rate less data than the native amount of the drive ?<BR /><BR />Any Idea ?<BR /><BR />I use ArcServe 2000 SP3 on a Win2k Server SP2, the SCSI Controller is an Adaptec AIC7880 UW (also tried with an Adaptec Ultra160)<BR /><BR /> Fri, 19 Jul 2002 05:49:08 GMT https://community.hpe.com/t5/storeever-tape-storage/problems-with-hardware-compression-c1537a-dds3/m-p/2767773#M4172 Andi_2 2002-07-19T05:49:08Z https://community.hpe.com/t5/storeever-tape-storage/problems-with-hardware-compression-c1537a-dds3/m-p/2767774#M4173 Hello,<BR /><BR />How did you set the switches 1 and 2 (controlling compression)?<BR /><BR />Switch 1 should be set to 1 to enable compression. Switch 2 should be set to 1 as well for Host control.<BR /><BR />HTH,<BR />Vince Fri, 19 Jul 2002 11:38:50 GMT https://community.hpe.com/t5/storeever-tape-storage/problems-with-hardware-compression-c1537a-dds3/m-p/2767774#M4173 Vincent Farrugia 2002-07-19T11:38:50Z https://community.hpe.com/t5/storeever-tape-storage/problems-with-hardware-compression-c1537a-dds3/m-p/2767775#M4174 hi<BR />-Conpression of data depend of the data itself, now a days, the data on a server are already optimized and have a low ratio in compression, you can check this, with an utility like winzip, that use a software algoritm to compress data, then compare your data with the result of winzip plus 5 - 10 % value (because Backup Software ad some header and catalogs on the tape).<BR />-Another thing that can create problem is if you have enabled the software conpression, then the data will be sent to the DAT already compressed, then no more compression allowed.<BR />-If you have an old tape or a head problem on your dat, this can worst space due to bad blocks.<BR />-The transfer rate is right, about one Mb/sec id the commom transfer rate for a DDS3 Tape Device.<BR /><BR />bye<BR /><BR />marino Fri, 19 Jul 2002 12:15:49 GMT https://community.hpe.com/t5/storeever-tape-storage/problems-with-hardware-compression-c1537a-dds3/m-p/2767775#M4174 Marino Meloni_1 2002-07-19T12:15:49Z https://community.hpe.com/t5/storeever-tape-storage/problems-with-hardware-compression-c1537a-dds3/m-p/2767776#M4175 Andi,<BR /><BR />If you are writing uncompressable files they will actually take up more room on the tape than if you didn't compress the files.<BR /><BR />A DDS-3 tape can store 24GB of data PROVIDING it can be COMPRESSED into 12GB. <BR /><BR />this means the tape can only really store 12GB!<BR /><BR />live free or die<BR />harry Fri, 19 Jul 2002 13:32:47 GMT https://community.hpe.com/t5/storeever-tape-storage/problems-with-hardware-compression-c1537a-dds3/m-p/2767776#M4175 harry d brown jr 2002-07-19T13:32:47Z