Thanks for the information, I will play with some test backups and see, also install sg_utils and check.
Thanks a lot, Frank bro...@mlds-networks.com schrieb am Freitag, 25. Dezember 2020 um 19:18:08 UTC+1: > Found the command it’s > > sg_logs -a <device> > sg_logs -a /dev/sg5 > > <lots of data> > Data compression page (LTO-5 specific) [0x32] > Read compression ratio x100: 109 > Write compression ratio x100: 100 > > > You can see I’m not compressing at all because I’m doing client side > compression (backing up over home networks) > > You can also compare the bareos volume size to > > Tape capacity page (LTO-5 and LTO-6 specific) [0x31] > Main partition remaining capacity (in MiB): 46592 > Alternate partition remaining capacity (in MiB): 0 > Main partition maximum capacity (in MiB): 800226 > Alternate partition maximum capacity (in MiB): 0 > > Which is the native capacity, if your volume is larger than your actual > consumed your compression is working. > > Brock Palen > bro...@mlds-networks.com > www.mlds-networks.com > Websites, Linux, Hosting, Joomla, Consulting > > > > > On Dec 25, 2020, at 12:58 PM, Brock Palen <bro...@mlds-networks.com> > wrote: > > > > Also compression look up the mt commands. But most are on by default. > Only encryption is anything you need to mess with in bareos. Again if doing > client compression you won’t see much if any on the tape side. If your not > you should see it. > > > > You can verify how much compression your getting two ways. One is the > volume size bareos reports being larger than the 6T native size. > > > > The other is look at the sg_* commands. One will read ann the drive and > currently loaded tape data. One will tell you compression ratio read / > written for the tape. > > > > Sent from my iPhone > > Brock Palen > > 989-277-6075 <(989)%20277-6075> > > > >> On Dec 25, 2020, at 12:53 PM, Brock Palen <bro...@mlds-networks.com> > wrote: > >> > >> I wouldn’t bother. Modern LTO drives (any made in lay 10 years) auto > detect end of volume. I do t use this setting at all with my two drives and > it auto sorts it out. > >> > >> This is important because the 15T quoted assumes compression of a given > ratio. That can very drastically. If you use client side compression you > won’t see any compression at all. Similar if most your data are video and > doesn’t compress well. If it’s all text emails you will get more than > listed. > >> > >> Let the drive auto detect and it will work the best. I think this is > one of the things you can test with the btape command. Highly recommend you > run all the tests in btape abd make sure they pass. > >> > >> I only use max volume size with disk volumes. > >> > >> Sent from my iPhone > >> Brock Palen > >> 989-277-6075 <(989)%20277-6075> > >> > >>> On Dec 25, 2020, at 12:38 PM, 'Frank Cherry' via bareos-users < > bareos...@googlegroups.com> wrote: > >>> > >>> > >>> Hello there, > >>> > >>> I'm storing on Ultrium 7 LTO tapes with a single drive unit. > >>> It is right, to set in the pool config the > >>> > >>> Maximum Volume Bytes = 15000G # Limit Volume size to something > reasonable > >>> > >>> to 15000G ? The tape is specified with 6 / 15 TB (uncompressed / > compressed) > >>> > >>> Is the tape drive works as default with compression? How can I check > it and can I define it on the SD config? > >>> > >>> Thanks, Frank > >>> > >>> -- > >>> You received this message because you are subscribed to the Google > Groups "bareos-users" group. > >>> To unsubscribe from this group and stop receiving emails from it, send > an email to bareos-users...@googlegroups.com. > >>> To view this discussion on the web visit > https://groups.google.com/d/msgid/bareos-users/f7fef681-396f-47dc-8a76-6a28547e7caan%40googlegroups.com > . > > -- You received this message because you are subscribed to the Google Groups "bareos-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to bareos-users+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/bareos-users/22f744b7-dd1e-43ba-850e-cb4c287d81c7n%40googlegroups.com.
