search for: subvolumes_and_snapshot

...dd if=/dev/sdb of=os.img bs=1M count=3210 That looks plausible. (I haven?t verified your count parameter exactly.) However, I wonder why you?re trying to reinvent snapshots, a technology now built into several advanced filesystems, such as btrfs and ZFS? https://en.wikipedia.org/wiki/Btrfs#Subvolumes_and_snapshots btrfs is built into CentOS 7. While there have been some highly-publicized bugs in btrfs, they only affect the RAID-5/6 features. You don?t need that here, so you should be fine with btrfs. And if you really distrust btrfs, ZFS is easy enough to integrate into CentOS on-site. And if *that* is...

I am building a mailserver and with all the steps, I want to image the drive at various 'checkpoints' so I can go back and redo from a particular point. The image is currently only 4GB on a 120GB drive. Fdisk reports: Disk /dev/sdb: 111.8 GiB, 120034124288 bytes, 234441649 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size

...mg bs=1M count=3210 > That looks plausible. (I haven?t verified your count parameter exactly.) > > However, I wonder why you?re trying to reinvent snapshots, a technology now built into several advanced filesystems, such as btrfs and ZFS? > > https://en.wikipedia.org/wiki/Btrfs#Subvolumes_and_snapshots > > btrfs is built into CentOS 7. While there have been some highly-publicized bugs in btrfs, they only affect the RAID-5/6 features. You don?t need that here, so you should be fine with btrfs. > > And if you really distrust btrfs, ZFS is easy enough to integrate into CentOS on-site....