a (hopefully) simple newbie zfs query regarding available space
Hello list I followed instructions for ZFS on http://wiki.freebsd.org/ZFSQuickStartGuide, substituting ad6 and ad10 (two new SATA3 1TB disks) for da0 da1 and da2 in the instructions. I was surprised to see only 993GB in /tank/. Is this expected, or is it user error? Also, these disks are completely unformatted. I expected to do a newfs or something similar, and for it to take a bit of time! This is on a running 7.2-STABLE amd64 system. It is only these two disks that I want as ZFS, the rest are UFS2 cheers -- John ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re: a (hopefully) simple newbie zfs query regarding available space
2009/8/9 John . comp.j...@googlemail.com: Hello list I followed instructions for ZFS on http://wiki.freebsd.org/ZFSQuickStartGuide, substituting ad6 and ad10 (two new SATA3 1TB disks) for da0 da1 and da2 in the instructions. I was surprised to see only 993GB in /tank/. Is this expected, or is it user error? Also, these disks are completely unformatted. I expected to do a newfs or something similar, and for it to take a bit of time! This is on a running 7.2-STABLE amd64 system. It is only these two disks that I want as ZFS, the rest are UFS2 cheers -- John I think I might have answered my own questionj - seems we need 3 or more disks for raidz - (n-p)*x gives 1TB usable. reliability isn't that important, and they are new disks. I suppose ccd would be better in this scenario? -- John ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re: a (hopefully) simple newbie zfs query regarding available space
2009/8/9 John . comp.j...@googlemail.com Hello list I followed instructions for ZFS on http://wiki.freebsd.org/ZFSQuickStartGuide, substituting ad6 and ad10 (two new SATA3 1TB disks) for da0 da1 and da2 in the instructions. I was surprised to see only 993GB in /tank/. Is this expected, or is it user error? Also, these disks are completely unformatted. I expected to do a newfs or something similar, and for it to take a bit of time! This is on a running 7.2-STABLE amd64 system. It is only these two disks that I want as ZFS, the rest are UFS2 cheers -- John ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org not a zfs thing is happens with all os and file systems. Basically HD manufacturers quote their capacities in base 10 ie 1 TB = 10 bytes. File systems are calculated in binary therefore the calculation they use is 1024 x 1024 x 1024 = 1099511627776. Slightly more as you can see. Therefore 1 GB is os terms is 1073741824 therefore hd capacity in GB is 1/1073741824 = 931.322575 The extra you see is it due to HD manufactures slightly over capacity the drives ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re: a (hopefully) simple newbie zfs query regarding available space
2009/8/9 chris scott kra...@googlemail.com: not a zfs thing is happens with all os and file systems. Basically HD manufacturers quote their capacities in base 10 ie 1 TB = 10 bytes. File systems are calculated in binary therefore the calculation they use is 1024 x 1024 x 1024 = 1099511627776. Slightly more as you can see. Therefore 1 GB is os terms is 1073741824 therefore hd capacity in GB is 1/1073741824 = 931.322575 The extra you see is it due to HD manufactures slightly over capacity the drives Hi, What I meant was, I was seeing 931MB instead of 1.6TB (2x1TB disks) but this was because I didn't read about zfs properly (they recommend 3 or more disks. In the man page for zpool it says: A raidz group with N disks of size X with P parity disks can hold approximately (N-P)*X bytes [...] The recommended number is between 3 and 9 so, I'll wait till I get an array before implementing zfs. In the meantime, I'm using gconcat. Sorry for the noise. -- John ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re: a (hopefully) simple newbie zfs query regarding available space
2009/8/9 John . comp.j...@googlemail.com 2009/8/9 chris scott kra...@googlemail.com: not a zfs thing is happens with all os and file systems. Basically HD manufacturers quote their capacities in base 10 ie 1 TB = 10 bytes. File systems are calculated in binary therefore the calculation they use is 1024 x 1024 x 1024 = 1099511627776. Slightly more as you can see. Therefore 1 GB is os terms is 1073741824 therefore hd capacity in GB is 1/1073741824 = 931.322575 The extra you see is it due to HD manufactures slightly over capacity the drives Hi, What I meant was, I was seeing 931MB instead of 1.6TB (2x1TB disks) but this was because I didn't read about zfs properly (they recommend 3 or more disks. In the man page for zpool it says: A raidz group with N disks of size X with P parity disks can hold approximately (N-P)*X bytes [...] The recommended number is between 3 and 9 so, I'll wait till I get an array before implementing zfs. In the meantime, I'm using gconcat. Sorry for the noise. -- John ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org ah did you do a zpool create tank ad0 then zpool attach tank ad1 type thing? if you did you have you have created a mirror to fix do a zpool dettach ad1 then a zpool add ad1 to create a stripe Having said that it not good practice to have no redundancy. You could comprise by putting your important data on a dedicated file system then setting copies to 2 or 3 ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
