Re: question regarding geom labels
On Fri Mar 30 12, Warren Block wrote: > On Fri, 30 Mar 2012, Alexander Best wrote: > > >i have a question regarding a label for a swap partition. when should i do > >the > >labeling? after or before creating the partition scheme? > > > >when i label before creating the partition scheme, likes this: > > > >glabel label -v swap /dev/da0 > >gpart create -s GPT /dev/da0 > > > >i get the following warning: > > > >GEOM: da1: the secondary GPT header is not in the last LBA. > > > >which is obvious, because the label is being written into the last LBA and > >thus > >the backup GPT header gets written into the last-1 LBA. > > Right. Don't do that, the GPT backup header needs to be at the end of > the physical device. If you're using that whole disk for swap, there's > no need for a partition anyway. > > >if i create the partitioning scheme before labeling the device, like this: > > > >gpart create -s GPT /dev/da0 > >glabel label -v swap /dev/da0 > > > >or > > > >gpart create -s GPT /dev/da0 > >gpart add -t freebsd-swap /dev/da0 > >glabel label -v swap /dev/da0p1 > > > >the label gets written into da0 or da0p1 and is at constant risk of being > >overwritten by userdata. > > No. The swap device entered in /etc/fstab would be /dev/label/swap, > which is one block smaller than da0p1. That's the last-block metadata, > it's safe. thanks for the info. :) > > But if the whole disk is for swap, skip the partitioning entirely. ___ 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: question regarding geom labels
On Fri, 30 Mar 2012, Alexander Best wrote: i have a question regarding a label for a swap partition. when should i do the labeling? after or before creating the partition scheme? when i label before creating the partition scheme, likes this: glabel label -v swap /dev/da0 gpart create -s GPT /dev/da0 i get the following warning: GEOM: da1: the secondary GPT header is not in the last LBA. which is obvious, because the label is being written into the last LBA and thus the backup GPT header gets written into the last-1 LBA. Right. Don't do that, the GPT backup header needs to be at the end of the physical device. If you're using that whole disk for swap, there's no need for a partition anyway. if i create the partitioning scheme before labeling the device, like this: gpart create -s GPT /dev/da0 glabel label -v swap /dev/da0 or gpart create -s GPT /dev/da0 gpart add -t freebsd-swap /dev/da0 glabel label -v swap /dev/da0p1 the label gets written into da0 or da0p1 and is at constant risk of being overwritten by userdata. No. The swap device entered in /etc/fstab would be /dev/label/swap, which is one block smaller than da0p1. That's the last-block metadata, it's safe. But if the whole disk is for swap, skip the partitioning entirely. ___ 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"
question regarding geom labels
hi there, i have a question regarding a label for a swap partition. when should i do the labeling? after or before creating the partition scheme? when i label before creating the partition scheme, likes this: glabel label -v swap /dev/da0 gpart create -s GPT /dev/da0 i get the following warning: GEOM: da1: the secondary GPT header is not in the last LBA. which is obvious, because the label is being written into the last LBA and thus the backup GPT header gets written into the last-1 LBA. if i create the partitioning scheme before labeling the device, like this: gpart create -s GPT /dev/da0 glabel label -v swap /dev/da0 or gpart create -s GPT /dev/da0 gpart add -t freebsd-swap /dev/da0 glabel label -v swap /dev/da0p1 the label gets written into da0 or da0p1 and is at constant risk of being overwritten by userdata. cheers. alex ___ 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"
