This procedure may be helpful for backups of Linux VMs on the cloud. Some (most) service providers make it notoriously difficult to export VM images or snapshots out of the cloud.<\/p>\n\n\n\n
While it is still possible to perform an image backup using Clonezilla, again, not all service providers allow boot on an ISO for a given VM. In these cases, a helper volume should be added to the VM and have Clonezilla installed on it, and selected as the boot device. The original boot volume would then be backed-up to an image locally on the helper volume and exported out of the cloud after the process completes. Although that is the theory, I have not tested this specific process myself. Keep in mind that some providers VM instances only support one volume attached. Also, this process is a one-shot operation, and is hardly automated, and creates downtime.<\/p>\n\n\n\n
There are other block level device time consistent backup strategies you can try though if you use LVM and have space on the LVM group, it is possible to snapshot your volume, mount the snapshot, and have rsync transfer it over the network. Keep in mind that if the rsync process is initiated on the backup system rather than on the backed-up system, you’ll better have to use ssh or other remote command tools to perform snapshot creation and mount and then rsync, have a way to check for errors returned by these commands and then only initate rsync on the backup system. Then perform a post-backup remote execution to unmount the snapshot and destroy the snapshot. This whole process is a bit similar to the Windows VSS snapshot operation.<\/p>\n\n\n\n
For more information about this process, check :<\/p>\n\n\n\n
LVM snapshot Backup and restore on linux<\/a><\/p>\n\n\n\n If you don’t use LVM then you’ll have to resort to backups that are not time consistent (not frozen in time), but it is better than nothing. That is the object of this tutorial.<\/p>\n\n\n\n Download cygsetup and perform a full or a minimal install. For a minimal install, you’ll need SSH and Rsync as well as it’s dependencies.<\/p>\n\n\n\n Now you’ll have to choose between using rsync through a SSH encrypted channel, or through a rsync daemon running on the remote host to be backed up.<\/p>\n\n\n\n Using rsync through SSH for a full system backup requires a root login through SSH, and automating rsync with SSH will require a way to supply credentials automatically, unless using a public\/private key non interactive (passphrase less) authentication scheme.<\/p>\n\n\n\n In the case of SSH plain password authentication, supplying it to rsync can be done through sshpass, which exists as a Cygwin package, but I have not tested it myself in conjunction with rsync<\/p>\n\n\n\n http:\/\/www.cygwin.com\/packages\/summary\/sshpass.html<\/a><\/p>\n\n\n\n https:\/\/stackoverflow.com\/questions\/3299951\/how-to-pass-password-automatically-for-rsync-ssh-command<\/a><\/p>\n\n\n\n However, allowing SSH password root authentication plus storing its password as cleartext in a file for sshpass to use it is a huge security risk.<\/p>\n\n\n\n At least, with a passphrase less public\/private key pair, the problem amounts to securing the private key well on the filesystem. It will still be acessible (read only) in the user account context that runs the rsync\/ssh script on Windows.<\/p>\n\n\n\n For all these reasons, I find it preferable to use the rsync daemon on the remote system. Which allows to use a backup account instead of root.<\/p>\n\n\n\n The downsides however are that you need to open the rsync TCP port on the remote system and configure your firewalls in the connection path accordingly; and also rsync daemon does not encrypt traffic. If it is an issue, then use a VPN or an IpSec tunnel.<\/p>\n\n\n\n Edit the rsync daemon configuration file.<\/p>\n\n\n\n Here is a sample of the rsyncd.conf<\/p>\n\n\n\n As per the rsync manpage, rsyncd runs as root, and uid and gid parameters, which can be global to all rsync shares or share specific, specify the impersonated context of the rsync access to the filesystem.<\/p>\n\n\n\n Since we’ll perform a system wide backup, we’ll use root.<\/p>\n\n\n\n auth users specify the rsync users authorized to access the share. These users are rsync specific, not system users.<\/p>\n\n\n\n read only is used since no writes will be performed on the backed up system, unless you want rsync to upload some state file on the remote system after backup, as we won’t be using SSH, that is a trick way to signal something to the backed up system, without any remote execution.<\/p>\n\n\n\n hosts_allow is useful for a cloud VM that does not have firewalling options provided by the service provider.<\/p>\n\n\n\n The user login password pair is specified in \/etc\/rsyncd.secrets.<\/p>\n\n\n\n Use a strong password.<\/p>\n\n\n\n Next start the rsync daemon, check it runs and check its socket is listening on TCP port 873.<\/p>\n\n\n\n Then we’ll make rsync launch at system boot.<\/p>\n\n\n\n Change RSYNC_ENABLE to true to start the daemon at system startup through init.d<\/p>\n\n\n\n We’ll start by setting up the windows batch files that will prepare the cygwin environment and run rsync. Change <IP> with your remote system to be backed up IP or DNS name. This script assumes standard port 873<\/p>\n\n\n\n The default file is named CWRSYNC.CMD and should reside at the root of the cygwin64 base folder.<\/p>\n\n\n\n You’ll need to add a file named rsync_p in my example that contains the password specified for the backup user, matching the password defined on the rsync daemon host. This allows non interactive execution of rsync.<\/p>\n\n\n\n Place this file at the cygwin64 base folder level.<\/p>\n\n\n\n Secure that file well at the NTFS level.<\/p>\n\n\n\n itemize-changes will log in the rsync_sys.log the file operations performed on the system. It is useful for troubleshooting.<\/p>\n\n\n\nSetting up cygwin on Windows.<\/h3>\n\n\n\n
Setting up the rsync daemon on linux Debian<\/h3>\n\n\n\n
apt-get install rsync<\/code><\/p>\n\n\n\nvi \/etc\/rsyncd.conf<\/code><\/p>\n\n\n\nuid=root\ngid=root\n\n[share_system_backup]\n\tpath = \/\n\tcomment = system root\n\tread only = true\n\tauth users = backup\n\tsecrets file = \/etc\/rsyncd.secrets\n\thosts allow = <ip_of_backup_system><\/code><\/pre>\n\n\n\nvi \/etc\/rsyncd.secrets<\/code><\/p>\n\n\n\nbackup:346qsfsgSAzet<\/code><\/pre>\n\n\n\nrsync --daemon<\/code><\/p>\n\n\n\nps-auwx | grep rsync && netstat -nlp | grep rsync <\/code><\/p>\n\n\n\nvi \/etc\/default\/rsync<\/code><\/p>\n\n\n\nRsync configuration on Windows<\/h3>\n\n\n\n
@ECHO OFF\nREM *****************************************************************\nREM\nREM CWRSYNC.CMD - Batch file template to start your rsync command (s).\nREM\nREM *****************************************************************\n\nREM Make environment variable changes local to this batch file\nSETLOCAL\n\nREM Specify where to find rsync and related files\nREM Default value is the directory of this batch file\nSET CWRSYNCHOME=%~dp0\n\nREM Create a home directory for .ssh \nIF NOT EXIST %CWRSYNCHOME%\\home\\%USERNAME%\\.ssh MKDIR %CWRSYNCHOME%\\home\\%USERNAME%\\.ssh\n\nREM Make cwRsync home as a part of system PATH to find required DLLs\nSET CWOLDPATH=%PATH%\nSET PATH=%CWRSYNCHOME%\\bin;%PATH%\n\nREM Windows paths may contain a colon (:) as a part of drive designation and \nREM backslashes (example c:\\, g:\\). However, in rsync syntax, a colon in a \nREM path means searching for a remote host. Solution: use absolute path 'a la unix', \nREM replace backslashes (\\) with slashes (\/) and put -\/cygdrive\/- in front of the \nREM drive letter:\nREM \nREM Example : C:\\WORK\\* --> \/cygdrive\/c\/work\/*\nREM \nREM Example 1 - rsync recursively to a unix server with an openssh server :\nREM\nREM rsync -r \/cygdrive\/c\/work\/ remotehost:\/home\/user\/work\/\nREM\nREM Example 2 - Local rsync recursively \nREM\nREM rsync -r \/cygdrive\/c\/work\/ \/cygdrive\/d\/work\/doc\/\nREM\nREM Example 3 - rsync to an rsync server recursively :\nREM (Double colons?? YES!!)\nREM\nREM rsync -r \/cygdrive\/c\/doc\/ remotehost::module\/doc\nREM\nREM Rsync is a very powerful tool. Please look at documentation for other options. \nREM\n\nREM ** CUSTOMIZE ** Enter your rsync command(s) here\n\necho \"start\" >> c:\\scripts\\rsync_sys.log\ndate \/t >> c:\\scripts\\rsync_sys.log\ntime \/t >> c:\\scripts\\rsync_sys.log\n\nrsync --no-perms --itemize-changes --password-file=rsync_p -lrvcD --exclude={\"\/dev\/*\",\"\/proc\/*\",\"\/sys\/*\",\"\/tmp\/*\",\"\/run\/*\",\"\/mnt\/*\",\"\/media\/*\",\"\/lost+found\",\"\/root\/*\"} backup@<IP>::share_system_backup\/ \/cygdrive\/d\/BACKUPS_FROM_CLOUD\/SYSTEM >> c:\\scripts\\rsync_sys.log\n\ndate \/t >> c:\\scripts\\rsync_sys.log\ntime \/t >> c:\\scripts\\rsync_sys.log\necho \"stop\" >> c:\\scripts\\rsync_sys.log<\/code><\/pre>\n\n\n\n