2 thoughts on - Remote Update OS From 6 To 7

• I’ve seen many comments discouraging trying to do this, let alone trying to do it remotely (and I assume you don’t have IPMI, iLO or other ‘bare metal’ remote acess).

  However, the process does not involve yum upgrade, you can check the following link which seems to go through the process in detail:

  https://shaunfreeman.name/blog/upgrading-CentOS-6-5-to-CentOS-7-2

  Be sure to complete the backup, and be ready to travel to site, or have remote-hands to restore the backup should the process go wrong.

  Best Practice would be to configure a new CentOS 7 system, and ship it pre-configured ready for a data transfer and migration of service to the new system, the decomission the old system and have it sent back to you.

• Hi, Jerry,

  Jerry Geis wrote:

  Not a good idea. Here’s a better one, that we’ve used here: ideally from another system running C7 that’s the same hardware (otherwise, you need to rebuild the initrd). mkdir /new /boot/new rsync -HPavzx –exclude=/old –exclude=/var/log/wtmp $machine:/. /new/. rsync -HPavzx $machine:/boot/. /boot/new/.

  After the copy, check these files:

  /boot/new/grub/device.map – should list the correct device name for hd0
  /new/etc/fstab – should have the correct labels for file systems Do this, too:
  rsync -HPavzx /etc/sysconfig/network-scripts/ifcfg-eth*
  /new/etc/sysconfig/network-scripts rsync -HPavzx /etc/sysconfig/hwconf /new/etc/sysconfig rsync -HPavzx /boot/grub/device.map /boot/new/grub/
  rsync -HPavzx /etc/udev/rules.d/70-persistent-net.rules
  /new/etc/udev/rules.d/

  on the new machine, run

  find /new/var/log/ -type f -exec cp /dev/null {} \;

  f this system is using Linux RAID,

  rsync -HPavx /old/etc/md.conf /etc/

  Copy the original SSH keys:

  rsync -HPavzx /etc/ssh/ssh_host* /new/etc/ssh

  Finally, rotate:
  zsh zmodload zsh/files

  cd /boot mkdir old mv * old mv old/lost+found . mv old/new/* .

  # Root partition. cd /
  mkdir old mv * old mv old/lost+found .
  #mv old/root . — WHY?
  mv old/scratch . mv old/new/* .

  sync sync

  Make selinux reset all the security file labels

  touch /.autorelabel

  Reboot, and when it comes back up, rerun grub2-install….

  mark