Current Installation: CentOS 7.1503 with SerNet Samba 4 ver. 4.1.17 configured as Active Directory Domain Controller.
Current Installation: HP Workstation with dual Xeon quadcore cpu's and 4 x SATA hard drives NOT configured in RAID array.

New Installation: CentOS 7.1503 minimal install
New Installation: SuperMicro with single Xeon quadcore cpu and 4 x SATA hard drives configured in two pairs of RAID 1.

The Current Install is about 3.5 GB's and has my Samba 4 setup all solid and working well. I want to know if it's possible to simply:

- tar up the whole root partition
- put it on a USB drive
- boot the New server with a livecd and unpack the tar'ed root (/) from the USB drive into the New server root (/) filesystem.

Both installs used the automatic partitioning from anaconda, so /boot is on a separate partition and has a working initrd and kernel on each computer. Both CentOS installs are setup using the xfs filesystem on the root (/) partition.

I saw someone do it successfully once but they left out certain directories like /srv , /tmp , and /var.
But I'm not 100% certain which directories need to be left out of the tarball.

Has anyone done this before?
Do you know if it's doable?

Thanks for reading.

Directories to skip should be at least: /proc /sys /dev /tmp /var

There are a bunch of things to worry about when saving and restoring tar formats. Consider links, path and name length, timestamps, owners and attributes, sparse files, etc:
http://www.gnu.org/software/tar/manu...71.html#SEC138

Thank you, SmallPond! :-)

I'm reading through the tar link, very informative, and many issues I've overlooked.
But, I think it may work well because of the simplicity of my installation --

There's only one posix user account besides root, thus almost all files on the system are user: root group: root.
I'll be using the same version of tar on both the Current Installation and the New Installation.
All other user data will be mounted on the other set of hard drives and not a part of the base installation I'm un-tarring into (/).
I'll also update each server install prior to transfer so all base install items on both match x.y.z to x.y.z.

Thank you for your help.
Greatly appreciated.

After some review of the directories mentioned, I think it's necessary to include /var .
Critical parts of the samba 4 installation are stored under /var/lib/samba .
Without it, there's no more Active Directory Domain Controller, and I definitely want to avoid re-provisioning a new/different AD DC.

I have inatalled samba on centos 7 DC with server 2008 domain/forest functional level. I have tested that if one day it will die how do I recover. I saved smb.conf kerb5.conf, nsswitch.conf, hosts, resolve.conf, /etc/default/samba.conf files then tarred /var/lib/samva with cvpf options. on new server installed samba again promoted ad dc with same domain name raised domain/forest level it was installed with internal samba dns and made same installation restored config files than untarred /var/lib/samba and everything was working. sysvol and gpo was in /var/lib/samba.

may be this will help you.

Paul, thank you for sharing your restore procedure.
It looks very efficient too.
I have a question about the part where you promoted AD DC with same domain name.
Why did you need to do this?
And what commands did you use to do it?
Is that part necessary if you copied everything from the original provisioned AD DC?

Best regards.

I promoted with samba-tool domain provision --use-rfc2307 --interactive you are right may be it was not nesessary.

Yes my friend GPO and everything, database of ad are stored there so i tared everything for good backup.