On Tuesday 15 January 2019 15:06:41 Chris Albertson wrote: > DOn't worry about the amount of data from hourly backups. If nothing > is changed on the system then there is no data written to the backup > device. Only data that has changed relative to the last backup > interval is written. In an office files server this could be quite a > lot of data 9 to5but zero change at night. On a tiny system mostly > nothing changes. > > Also it does not matter how long the system has been running > continuously, what matters is how fast the data changes. Most all > backup system will delete older version if the backup disk is full so > the backup remains always the size of the disk. So for example as the > disk fills with hourly copies of some log file the system finds the > oldest logs and keeps only daily snapshots, then as the disk files it > keeps only weekly then monthly and yearly copies. So after this > runs a while you find you have hourly resolution only back to a point > and then it goes to weekly or monthly. The details depend on the size > of the backup disk. But almost always the system can be configured > to only a specified amount of space. As a rule of thumb your backup > disk is 2X the size of the data tube backup up. This works because > most files never change. > > This is the system Apple uses on Mac OS. Macs run BSD UNIX and there > are some Linux/Unix copies of Apple's system that you can download and > install. All of them do a good job of managing a fixed amount of > backup space. > > It is hard to say what is best. Perhaps you have a half dozen Linux > systems and some Windows PC notebooks and you want to centralize > backup to one server? The server then has to know how to talk to both > Windows and Linux clients. But other people have just one PC and > have simpler needs. So there is no "best" backup system. > > And then do you only have a few text files you care about or do you > have digital photos and video footage that add up to multiple > terabytes or more? Video cameras fill disks quickly. then the backup > device needs to be a RAID. > > Here are some links > https://www.ubuntupit.com/top-15-free-open-source-backup-software-for- >linux/ Google can find more. > > Some of the above can integrate the cloud storage services like > Backblaze or Amazon S3 Then you are 100% bomb proof, literally. You > keep a local versions backup and also a copy of the same off-site. > > On Tue, Jan 15, 2019 at 8:01 AM Jon Elson <[email protected]> wrote: > > On 01/14/2019 09:31 PM, Chris Albertson wrote: > > > The blu rays work but the backup internal is to long. It really > > > needs > > > > to > > > > > be done every hour. Hourly backup is best done with a hard drive. > > > > HOUR? Well, really, my Linux systems stay up a log time. I > > just rebooted my main desktop system after 540 days > > continuous running. My Asterisk phone system recently > > crashed and I had to do a manual fsck after about 15 months > > running. My main server (router/firewall, web, mail, ssh, > > dns, etc.) has been up 317 days. > > > > > A simple and painless way is to subscribe to a service. The guys > > > who run the the big cloud can buy storage cheaper then you can and > > > they have peta-bytes and do all the maintenance and upgrades for > > > you. > > > > I don't trust these cloud services. I had a cheap (but not > > free) secondary name server that went out of business with > > no warning or anything. I'd just done a 2-year renewal. > > Just one day their service stopped working. > > > > > One problem with using small media is that to restore it you have > > > to > > > > know a > > > > > lot. Typically each disc is only the delta from a full snapshot > > > so to restore you first restore the last ful image then you have > > > to restore > > > > each > > > > > change disc. > > > > True on my hard drive backup, NOT true on the blu-ray > > backup. Every one is a full backup. > > One of the problems with the incremental backup is if one of > > the deltas is seriously bad, like completely unreadable, you > > have a major mess to reconstruct what you can. And, if the > > last update to a file was on the bad delta, it is just gone, > > you only have the oldest version on the full backup. > > > > I don't consider a blu-ray as "small media". It is > > 22-something GB. It will hold pretty much all of my main > > user file tree. > > I have my pictures and various CNC manuals in another file > > tree, and back that up to another blu-ray. > > > > Jon > > I'm forced to comment here, because while I am a long term (about 20 years now) user of amanda, so I am quite familiar with its concept of doing a level 0 within the timeframe of runspercycle, usually stated in days, with a chefs choice of backup levels out to 4 or 5 used in between fulls, with an eye toward adjusting the schedule to always use the same amount of storage on the media during an individual run.
But no one has mentioned the name of something that will backup only the changes, that can be started in the background to accomplish this instant incremental backup while one is working on a project. Does linux actually have such a beast? Or is it generally a component of the development environment used. IOW, names please. Your own favorite poisons. What I'd expect to see at the base is inotifywait session's covering the directories involved with your project, that would immediately return the name of the file just written, which when that name is returned to the parent caller, which in turn causes the parent to make a one higher level backup of that file. Probably ought to have a button to make a new level 0 at the end of the days work if its working so far but incomplete. Something along those lines. But I don't see a utility like that in the repo's. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
