Relax and Recover(ReaR) / disaster recovery

Redhat give us a system back solution (ReaR), althought it is not supported by redhat, but it works. now we test it out.

reference:

  • https://access.redhat.com/solutions/2115051
# on nfs server yum install -y nfs-utils mkdir -p /storage cat << EOF > /etc/exports /storage *(fsid=0,rw,sync,no_root_squash,no_subtree_check,crossmnt) EOF cat /etc/exports # /storage *(fsid=0,rw,sync,no_root_squash,no_subtree_check,crossmnt) systemctl enable --now nfs systemctl disable --now firewalld # on target server yum install -y rear pstree nfs-utils cat << EOF > /etc/rear/local.conf OUTPUT=ISO OUTPUT_URL=nfs://192.168.203.134/storage BACKUP=NETFS BACKUP_URL=nfs://192.168.203.134/storage BACKUP_PROG_EXCLUDE=("${BACKUP_PROG_EXCLUDE[@]}" '/media' '/var/tmp' '/var/crash') NETFS_KEEP_OLD_BACKUP_COPY= EOF rear -d -v mkbackup # on nfs server, new files created from target centos7 vm tree /storage # /storage # └── target-centos7 # ├── backup.log # ├── backup.tar.gz # ├── README # ├── rear-target-centos7.iso # ├── rear-target-centos7.log # ├── selinux.autorelabel # └── VERSION # now destroy the target centos vm, and recreate a new one # boot the new vm using rear-target-centos7.iso

after reboot, the system comes back