What is e-smith-backup with dar ?e-smith-backup with dar is an upgrade of current e-smith-backup sme core rpm based upon use of dar program.
What provides e-smith-backup with dar ?e-smith-backup with dar completes core e-smith-backup with four panels :
- configuring daily backup to smbfs/cifs/nfs share on a LAN workstation or on local usb disk
- verifying backup on lan or local usb disk
- restoring full backup from lan or local usb disk
- selective restoring of files or directories from lan or local usb disk
New backup options are provided with additional perl functions included in backup panel script, a new perl backup script /etc/e-smith/events/actions/workstation-backup-dar, and a new backupwk record in configuration db. All are written with the same logic as present backup scripts, for seamlessly integration.
What are specific problems with LAN backups ?With more than one year use of e-smith backuping with dar on LAN workstations (in production environments) the most important of encountered problems is that, when the backup session is started, you cannot rely upon a perfect working of the LAN or the distant workstation.
Inevitably, one day the LAN is too busy and/or the connection to the distant share hacks. The result could be zombie backup or mount process, or even backups that do not complete before next daily backup session. These problems are problems of real world with LAN, that backup scripts must take into account.
Another common problem with backup through a LAN is that your lan disponibility for backup flow is not 24/24, but more probably something like "only from 20h to 6h, except on sunday where nobody works on the LAN..." So in case of large backup volume of datas, beeing able to backup all the datas during the week-end and doing only incremental backup on the week days really makes sense.
All these problems are considered with e-smith-backup with dar.
Scripts aim to verify absence of old zombie mounts of share, and alerts admin about such situation. No other assumption than "the distant backup share is available and writable" is made (and verifications are made for each access). With daily backup only a maximum backup time of 24 h is possible, and if this limit occurs the script cleanly stop the backup session (maybe the backup is working and in progress but has not enough time to complete), the lan share is unmounted, and daily process can restart anyway. If a precedent full backup was not completed because of a timeout (and if incremental backup is enabled) the backup can then safely restart and complete in an incremental way.
To limit when backup session occurs on the LAN, the admin user can set a timeout which keeps the session into a specified number of hours, allowing LAN backup sessions at periods where users don't work on the LAN. Admin user can also query for this time limit to occur only on incremental backup sessions. This permits to use, for instance, 24h on sunday to do full backup, and limit incremental backup sessions to 6 or 8 hours during week days. Full backup sessions can also be allowed on every day, or limited to a specific day of week.
Are other new functions provided ?Yes. Aside session timeout use, the first is
incremental backup.
This means that you can backup and restore datas for periods you want : one day, three days, one week, one month, 100 days... and restore your system at any state it was during this period of time. This probably has no utility to do full restore of the system as it was one month ago, but restoring a file lost by a user two or three weeks ago can be useful. And restoring a safe system more than one day old can be needed.
The second function is keeping more than one set of backup (a set is a full backup and all next daily incremental backups before a new full backup) with automatic rotation. In the simplest case you can, for example, do only nightly full backups but keep three sets of backup for security reason (as being able to restore the system as it was 72h ago).
The third function is
selective restore of any backuped file or directory, exactly as it was for any of the backuped days. Not only you can restore a lost file at his last state, but also say : make restore of the most recent version of the file before this given date... Selective restore is not an easy thing to manage and to provide in a simple way with panels. Dar permits to manage it. e-smith-backup with dar panels try to keep this function as simple as possible to use, without reducing offered capabilities.
Where to find e-smith-backup with dar ?Presently beta version of e-smith with dar can be uploaded at
http://beta.free-eos.org/sme/RPMS/e-smith-backup-1.14.0-14jplb01.el4.sme.noarch.rpm SRPMS available at
http://beta.free-eos.org/sme/RPMS/e-smith-backup-1.14.0-14jplb01.el4.sme.src.rpm Dar rpm is available at
http://beta.free-eos.org/sme/RPMS/dar-2.3.1-1.i386.rpm or
http://mirror.contribs.org/smeserver/contribs//dmay/smeserver/7.x/testing/dar-2.3.1-1.i386.rpmI read problems about smbfs or cifs support with sme, and nfs packages are not on my sme...Yes, present sme7 smb and kernel versions of have bugs for smb and cifs support. For smb mount bug, e-smith-backup with dar includes necessary work-around. For cifs, if the problem occurs, update to SME 2.6.9-55 kernel (this is a bug in older SME kernel). For nfs support, e-smith-backup doesn't need install of any nfs package on the sme server (not even portmap).
Comments are welcomed.
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sme 7.1 version
sme 7.1.1 version
sme 7.1.3 version
7 Jun 2007 : updated version