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RE: [CentOS] Best backup software for linux
by Mark Schoonover 07 Nov '06

07 Nov '06

Les Mikesell wrote: > On Mon, 2006-11-06 at 14:54 -0800, Mark Schoonover wrote: > >>> Note that this only works as a backup if the original filename is >>> removed. If it is overwritten or truncated instead, all links now >>> point to the changed version. >> >> This is true if you're doing it with only filesystem tools, but this >> system is using rsync. What's happening is the cp -al occurs first >> making hardlinks that point to an hourly directory into the current >> directory, then rsync is run to update current. Because rsync will >> create a new temp file when any file changes, the original is >> deleted with it's data 'pushed' to any hardlinks pointing at the >> original file. Rsync then renames the temp file the original file >> name that has changed, therefore assuring that any hardlinks will >> always have the previous copy of any changed files. With rsync >> running in --delete mode, any files from the source server that get >> deleted, will get deleted out of current in the backup server, >> causing this cascade of hardlinks to get updated with the deleted >> files data. That's how this system can create incremental backups of >> only changed data, but with hardlinks, it looks like full backups >> are made each and every time. Really saves disk space, that's for >> sure! >> >> Hope this clears things up... > > Backuppc is even more extreme in the space savings. It first > compresses the files, then detects duplicates using an efficient > hashing scheme and links all duplicates to one pooled copy whether > they came from > the same source or not. It includes a custom rsync on the server > side that understands the compressed storage format but works with > stock versions on the remote side so you don't need any special client > software. And it has a nice web interface for browsing the backup > archive and doing restores. Sounds like a good product! Since I had plenty of terabytes of storage, having compression on the files wasn't a requirement. One of my requirements was not having a gui to configure things, or do restores. Thanks for pointing some info out on backuppc, I've never heard of it. Mark

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onboard adaptec SAS RAID controller not seeing drive(s)
by Steve Finley 07 Nov '06

07 Nov '06

I have a Supermicro SuperServer 6025B-3V with their X7DB3 mobo. It has an onboard Adaptec SAS RAID controller and has been configured as a RAID1 with two Seagate Cheetah 15k.4 disks. Original attempts at installing CentOS4.4 x86_64 appeared to load the aic94xx driver, but then reported something like "No hard drives found...". I grabbed the x86_64 aacraid driver disk from Adaptec (updated 23 OCT 2006) and tried a "linux dd" install. Although the driver disk appears to load, I still get the "No hard drives found.." message. I'm waiting for a response from Supermicro, but any advice from this list (including a controller that works) would be greatly appreciated. Thanks, Steve Finley

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RE: [CentOS] Best backup software for linux
by Mark Schoonover 06 Nov '06

06 Nov '06

Les Mikesell wrote: > On Mon, 2006-11-06 at 18:42 +0000, Peter Crighton wrote: > >> You wrote "Hardlinks are key to this backup strategy. Using cp -al >> creates hardlinks to files, and this simple command is what does all >> the heavy lifting for daily and weekly backups. Wikipedia has a very >> good explanation on how hardlinks work. In a nutshell, when there's a >> hardlink pointing to a file from the hourly directory, to a file in >> the current directory, and that current file gets deleted, all the >> links that point to that now deleted current file gets the file data >> 'pushed' back towards all the links. I'll have to think how to >> explain this better." >> >> Do you mean that the hourly files are written when created, the >> hardlink for the daily doesn't actually copy the file (simply makes a >> link), but if the file is set to be deleted from it's location >> (because it's gone from the server) then it is actually moved so that >> it still exists in the daily backup but is removed from the hourly? >> -- > > Think of all directory entries as links. The real entries that > map disk space to files are inodes and links are names pointing > to the inodes. There can be any number - including 0 - of links > to an inode. The space is not released for re-use until the > link count goes to 0 and no process has the file open. So hardlinks > are just multiple names pointing to the same data, and the data > doesn't go away until the last name is removed. You did much better explaining what's going on with hardlinks than I did. I'm going to have to rewrite that part of the blog a few times before it reads better. I can picture it all in my head, but describing how it works is another. >Note that this only works as a backup if the original filename is removed. If it >is overwritten or truncated instead, all links now point to the changed version. This is true if you're doing it with only filesystem tools, but this system is using rsync. What's happening is the cp -al occurs first making hardlinks that point to an hourly directory into the current directory, then rsync is run to update current. Because rsync will create a new temp file when any file changes, the original is deleted with it's data 'pushed' to any hardlinks pointing at the original file. Rsync then renames the temp file the original file name that has changed, therefore assuring that any hardlinks will always have the previous copy of any changed files. With rsync running in --delete mode, any files from the source server that get deleted, will get deleted out of current in the backup server, causing this cascade of hardlinks to get updated with the deleted files data. That's how this system can create incremental backups of only changed data, but with hardlinks, it looks like full backups are made each and every time. Really saves disk space, that's for sure! Hope this clears things up... Mark

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pptp + iptables + centos
by Sherwyn Greene 06 Nov '06

06 Nov '06

Hi, All I'm tring to get a client connected to a vpn server running pptp & centos, the client connects to the server but I can't browse the internet or the local network from the client, when I stop the firewall the client can ping the server but no browsing can be done, do I need a iptables rule to allow pptp clients to use the internet or browse the network??? Sherwyn Greene Planner / I.T. Technician Project Controls Dept. Kentz-OJ's E&I Services J.V. +1 (868) 648-0876

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RE: [CentOS] Best backup software for linux
by Mark Schoonover 06 Nov '06

06 Nov '06

Jeff Stacey wrote: > On Fri, 2006-03-11 at 10:28 -0800, Bbt Lists wrote: >> Mark Schoonover wrote: >>>>>>> Maybe this is something I should write up in more detail. The >>>>>>> entire system runs on just a couple of shell scripts, rsync, and >>>>>>> Perl program to mail out logs.... >>>>>>> >>>>>>> HTH >>>>>>> Mark A day late, but ran into some problems with blogspot. The article is posted at: http://marks-tech-pages.blogspot.com - titled Linux Based Poor Man's SAN. Let me know what you think! Thanks! Mark Schoonover IS Manager American Geotechnical V: 858-450-4040 - F: 714-685-3909 - C: 858-472-3816 "Stop the Earth!! I want off!!"

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RE: [CentOS] Best backup software for linux
by Bowie Bailey 06 Nov '06

06 Nov '06

Mark Schoonover wrote: > From: Les Mikesell [mailto:lesmikesell@gmail.com] > > On Fri, 2006-11-03 at 07:51 -0800, Mark Schoonover wrote: > > > > > > Maybe this is something I should write up in more detail. > > > > > > The entire system runs on just a couple of shell scripts, > > > > > > rsync, and Perl program to mail out logs.... > > > > > > > > > > > If you do by chance write that up, I would be interested in > > > > > seeing it. Dustin > > > My goal is to have the rough draft posted on my blog later today. > > Do you have a comparison to backuppc > (http://backuppc.sourceforge.net/)? > > No, but you can read my blog, then look at backuppc and see what the > differences are. Let us know. Sounds interesting. Where is your blog? -- Bowie

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RE: [CentOS] Best backup software for linux
by Mark Schoonover 06 Nov '06

06 Nov '06

-----Original Message----- From: Les Mikesell [mailto:lesmikesell@gmail.com] Sent: Monday, November 06, 2006 8:59 AM To: CentOS mailing list Subject: RE: [CentOS] Best backup software for linux On Fri, 2006-11-03 at 07:51 -0800, Mark Schoonover wrote: > >>>> Maybe this is something I should write up in more detail. The > >>>> entire system runs on just a couple of shell scripts, rsync, and > >>>> Perl program to mail out logs.... > >>>> > >>> If you do by chance write that up, I would be interested in seeing > >>> it. Dustin > My goal is to have the rough draft posted on my blog later today. Do you have a comparison to backuppc (http://backuppc.sourceforge.net/)? No, but you can read my blog, then look at backuppc and see what the differences are. Let us know. Mark

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RE: [CentOS] Best backup software for linux
by Mark Schoonover 06 Nov '06

06 Nov '06

>>>> Maybe this is something I should write up in more detail. The >>>> entire system runs on just a couple of shell scripts, rsync, and >>>> Perl program to mail out logs.... >>>> >>>> HTH >>>> Mark >>>> >>>> >>> If you do by chance write that up, I would be interested in seeing >>> it. Dustin >> >> Agreed! Hints about where you put the snapshot files, how you are >> mounting the NAS, the commands you use to generate the snapshots, >> etc. would be most helpful. I know that each of these pieces are >> documented sparerately, but gathering this stuff you do into a nice >> little recipe can be very helpful to other folks. My goal is to have the rough draft posted on my blog later today. Mark

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Lstat & Dovecot
by Dave J. Hornford 06 Nov '06

06 Nov '06

I am chasing a problem with dovecot generating an error: lstat(/var/spool/virtual_mailboxes/[domain dir]/[user dir]/Maildir/cur) failed: Permission denied I first tried making the directory world readable, same error. Them tried to lstat [the path] at the console and receive the error: lstat: command not found I have a manpage on lstat, but no file. "Yum provides" showed the manpages, but no rpm I could find What rpm is it in? (Or, have I started down a path that doesn't involve this application & Dovecot isn't clear) Thanks Dave

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Fwd: How to grep and remove files
by Indunil Jayasooriya 06 Nov '06

06 Nov '06

Hi All, I want to know how to grep and delete (remove) files . What I need is that there are some unwanted out going mails in the queue in my Centos 4.4 Sendmail Server. I can find them with the below commad. mailq /var/spool/mqueue/ |grep '<>' Then It displays all the mails of that type withg their ids in the following way. [root@gateway ~]# mailq /var/spool/mqueue/ |grep '<>' kA63ZwJT007450 13864 Mon Nov 6 09:05 <> kA63LqO3004442 4110 Mon Nov 6 08:51 <> kA63V7Tn006327 16913 Mon Nov 6 09:01 <> kA62vH4t031111 13880 Mon Nov 6 08:27 <> kA62r6WW030077 13975 Mon Nov 6 08:23 <> kA63BxYQ002455 16443 Mon Nov 6 08:41 <> kA62MW0w023058 13536 Mon Nov 6 07:52 <> kA62jQah028236 13625 Mon Nov 6 08:15 <> kA62gLTw027445* 13710 Mon Nov 6 08:12 <> kA62JXwd022569 13849 Mon Nov 6 07:49 <> kA62idkg028035 13949 Mon Nov 6 08:14 <> kA62PEHX023554* 14152 Mon Nov 6 07:55 <> kA62W7Dd024920 14203 Mon Nov 6 08:02 <> kA62TtJn024569 14245 Mon Nov 6 07:59 <> kA62TU2j024446 14262 Mon Nov 6 07:59 <> kA62ZL0E025726 15878 Mon Nov 6 08:05 <> kA62MW6J023059 17106 Mon Nov 6 07:52 <> kA6266rV019846 13678 Mon Nov 6 07:36 <> kA62FXCd021741 13693 Mon Nov 6 07:45 <> kA626v5u020008 13718 Mon Nov 6 07:36 <> kA62X36L025101 13873 Mon Nov 6 08:03 <> kA62Xd6u025234 13901 Mon Nov 6 08:03 <> kA62RMT8023973 14008 Mon Nov 6 07:57 <> kA62Ufi6024703 14014 Mon Nov 6 08:00 <> kA62JxSm022664 14044 Mon Nov 6 07:49 <> kA62Q0Sd023738 14057 Mon Nov 6 07:56 <> kA62VgKI024882 14116 Mon Nov 6 08:01 <> kA62QmtQ023890 14129 Mon Nov 6 07:56 <> kA623NxG019271 13740 Mon Nov 6 07:33 <> kA620tLk018801 14004 Mon Nov 6 07:30 <> kA61q1PS017035 14094 Mon Nov 6 07:22 <> kA6215S7018835 14154 Mon Nov 6 07:31 <> kA61kYX8015811 13536 Mon Nov 6 07:16 <> kA61c63T014124 13811 Mon Nov 6 07:08 <> kA61WhXL013089 10232 Mon Nov 6 07:02 <> Now I want to know how to remove them. Then I can set up a crontab to do it evey 5 minutues. Any help .. pls -- Thank you Indunil Jayasooriya -- Thank you Indunil Jayasooriya

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