My Linux Experiences |
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Last update: September 5, 2010 |
| October 20,
2004 About a year ago I got the bug to try out Linux. I had upgraded my main PC and had a "spare" P2-333 machine with 256 MB and a 4 gig hard drive just begging to be used. The First Install - Redhat 9I did a lot of research before I settled on this distribution but figured it was only an experiment and I could always just wipe the hard drive and start with something else later. It turns out that it all worked pretty good with the default install but there was some stuff that didn't come out the way I expected. I couldn't get Samba to play nice with the rest of my windows network and soon became frustrated. I wiped it and reinstalled thinking there was a problem with the install but no good - still broke. During this install I got a clue though - there's a FIREWALL turned on by default when you install and that turns out to be what was blocking the Samba traffic. Once I turned the firewall off (didn't need it) all worked just fine.I played with the apps (and games) in Gnome and finally got around to thinking about the web server, Apache. Turning it on was easy and I found that it was pretty straightforward after that to load up my web content. I opened up port 80 on my router and pointed it at the server and could access it from the outside world. OK, but it's not nice to have to know one's changing DSL IP address whenever you wanted to access the web page. I had at one time set up PCAnywhere on my windows PC and used the services of no-ip.com to route from an external name to my PC. It worked just fine with my web server too so now I was available from the outside. The End of RedhatWell, Redhat decided that they wanted to get out of the "free" business. I never really was happy with their support policy and even less so with the Fedora project support so I started looking for something else. I had another PC around - AMD K5-166 with 64 MB of RAM so I started looking for something different and perhaps better.I looked at quite a few - Fedora, Debian, Slackware, and SuSE. Except for SuSE I was able to download the full ISO image and install what I wanted - Apache and Samba with no GUI interface. I tried them all but was not particularly satisfied with the results. One of my major goals was simple patches and none of these fit. I could never get SuSE 8.2 to do an FTP install with the 64 Meg of RAM and more was not possible so I never really got anywhere with SuSE. The Trustix Solution
At long last I found one that was a bit of an odd distribution - Trustix.
It had the features and easy update facilities I wanted and it didn't
even have GUI options. I got it up and running pretty easily and was
able to easily switch over my web and Samba services. The Redhat
machine then became history. |
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December 17, 2004 It's been a while since I updated this. The UPS is installed and working just fine. Nice to see what is really happening with my power. Also nice to see that it can really handle the short outages just fine. It would be interesting to know how it handles longer ones but I'm in no hurry to test it. I have a new plan for the Netware stuff. I've already copied some of the more static stuff that is mapped to other drive letters anyway to the Linux server. What's left will easily fit on the main drive of the linux server so that can happen most anytime. Once I get all the data moved I can shut down the Netware server and then move the drives as a mirrored pair to the Linux server. Then it's more shuffling of data and I'm done. Netware is then history - I'm sorry to see it go but it's time seems to have passed for me and my customers. |
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December 29, 2004 Today was RAID day. I had fired up the backup server a couple of days ago and rsync was doing it's thing quite nicely. I switched the router to us the backup and then shut down the main server. I then installed the two 4.3 GB SCSI drives that were Netware drives in the server along with an Adaptec 2940W card. Boot up the system and it all hangs while trying to load the drivers for the old Adaptec 1542 card. Pulling the 1542 card solved the problem - some conflict there. I evaded the issue by pulling the internal tape drive that was in the Netware server and installed it in the Linux server cabled from the 2940W card. It all booted up just fine and the hardware all works at this point. Now to build the RAID array - not all that tough. Ran cfdisk and set up the two "RAID" partitions and coded the raidtab from as directed in a very nice tutorial at: "The Software-RAID HOWTO". Went to run mkraid and it says it couldn't do it because there was no "chunk size" specified. Well, the example I had didn't include it and the man page for mkraid isn't all that helpful so I just put one in and it all worked just swell. Only took around 7.5 minutes to sync the two drives up so the performance is pretty good. Then built the file system (reiserfs) and set up a mount point. All is going just great and this part is working well. Moved the data over to the array and fixed up the Samba parameters and it all seems to work great. I decided it would be good to run a backup so I fired it up and ... no-go. Says "excessive retries" so I'm wondering if that seldom used tape drive is dead. It does rewind and eject the cart just fine so it's not completely out of it so I try the obvious - run a cleaner cart through it. That does the trick and all is well. Ran the cleaner cart again after the backup (tape drive says so - slow blinking green light) and all seems to be well. Ran into yet another Samba issue. Turns out people in the group for the directory can't delete existing files because they don't own them (root does). There's a parameter "create mask" that is comes into play whenever you create or delete a file. This mask is "and-ed" on the file system rights and the result is what is applied. The default is "0755" which lets the owner do it but not the group even if they have the file system rights. I set up a global default for this mask to "0777" which then lets me do the controls I need at the file system level like I expect to. |
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January 24, 2005 Well, about 9:35 PM on January 5th I got my wish. We had nasty freezing rain that caused widespread power outages in the area. The UPS ran for about 55 minutes and apcupsd nicely handled a clean shutdown. Unfortunately the UPS itself didn't get shut down. Because of this there was no power off/on for the PC power supply to see and therefore when the power came back the server didn't. I was still up 2 1/2 hours later when the power came back so I got things manually restarted. It was late so I figured I'd check on why the UPS wasn't turned off the next day. About 2:50 the next morning the power went out again. This time the batteries lasted about 20 minutes - not all that bad for only 4 hours charge time. Of course I wasn't awake at the time so the server was still off when I got up the next morning. I got it back up and running and then tracked down the problem. It seems that the "halt.local" script that is installed with apcupsd has an "if" statement testing for "START_APCUPSD" variable set to "yes" but nothing ever sets this variable. Searching the web I found references to this variable but it looks like the setting of it was removed some time ago. The solution I came up with was to comment out the "if" statement (and the ending "fi"). So far it hasn't been tested and I'm in no hurry. |
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May 2, 2005 It's been a little while but I haven't been idle - just busy with other things. Things are running pretty smoothly actually so not much to do except keep up with patches. I've added a host or two to Apache but otherwise not a lot new. I've been reading Learning Perl (the Llama Book) and starting to actually understand Perl. I've been generating a flat file version of the FCC Amateur callsign database every week and I can access it with a C program I wrote some time ago. On reading about Perl I started thinking that I could write this program in Perl and then make a CGI script of it so I could use it via the web. Well, it actually works (after a fashion) and I'm anxious to finish off the book so I can move on the the next book: Perl DBI. I have plans for a MySQL database and web pages sometime in the future. Another change is to change the mail server to send mail via my ISP. I was getting tired of this server or that refusing to talk to my mail server because somebody in my subnet was bad. And then AOL decided they were going to block my ISP's email server - for probably the fourth time in the last year or so. I sent everyone on my mailman mailing lists a note saying "get off AOL, set up a forwarding service, or set up a yahoo email account or expect to loose emails". I refuse to waste any more of my time worrying about AOL users not getting email I sent. If they get it, fine. If not, I'm not really going to care. The UPS shutdown software continues to be untested, but I can wait. Tape backups with TAR continue to work just fine when I remember to do them. I do backup critical stuff to the big storage volume automatically so it wouldn't be the end of the world if the main 4 Gig drive died without a current tape backup. I was using STAR for daily backups but found I could restore anything from them. Not good. Figured out how to get TAR to backup stuff from a specified date and got that to work just fine. I never did track down why I can't restore from a STAR backup and I probably won't bother with it. Think I'll just stick with gold old TAR. |
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May 14, 2005 The UPS "fix" (see January 24) does work! Unfortunately nobody can see this yet because the phone line (and DSL) is still down. Last night we had some severe weather go through and the neighbor's tree fell across the utility lines. Took out HV feed line and then yanked the 240 volt local feeders hard enough to snap the pole in my back yard in half. This also yanked my electrical service off the side of my house. Ohio Edison was out about 3 AM sawing enough of the tree out of the way to clear some things up. They planted a new pole and went to breakfast. By about 10 AM all their stuff was back up. Around that time SBC showed up and was amazed at how serious the problem was - this despite my telling the guy I reported it to last night exactly what had happened. As I write this, SBC is still "planning" what to do. You can look at http://ak8b.us/storm-may2005.htm for more info. |
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December 17, 2005 Way too long since the last update. If I can just remember all that I did ... I did finish the Llama Book and have a much better understanding of Perl. If you've used a programming language, particularly C, this is the book for you. Perl definitely looks a LOT like C and has a lot of really neat extras. There is also a very good (but not complete) discussion on how regular expressions work. Since MySQL has decided to associate themselves with SCO I have started looking at Postgres instead. I'm missing something as I can't seem to get it updatable from MS Access. I'm sure it's something silly but it's not real high priority yet either. It's installed and I fiddled with it a bit but that's it. Some day when I get serious about dumping MySQL I'll do something more. I only have one database right now anyway. A couple of weeks before my daughter and I were going on vacation this summer she asked about signing up for a service where we could upload pictures that everyone could see. I asked her to hold off until I looked for something I could run myself on my own server and she reluctantly agreed. It took me all of 5 minutes to find one called Gallery. I installed it and had it up and running in about an hour. Showed her how to use it and within a couple of hours she gave it her stamp of approval. At the time version 2.0 wasn't out so this is version 1.5 (I think) and works perfectly for our purposes. Another zero cost neat feature! Since Holiday Inn Express has free Wi-Fi we were able to upload stuff the same day for part of our vacation. Pretty neat! If you want to look it's at http://gallery.ak8b.us - remember it's only DSL so the uplink is not all that fast for the photos but it serves the purpose at no cost. I replaced the CD-ROM drive with a DVD-ROM drive so I can offload some of the more static stuff onto a DVD+RW disk. These are the CD image type things like the ham callbook and such. It was working just fine until the last kernel update a few days ago. I didn't notice at the time but the DVD would no longer mount. Finally tracked it down and it seems that this kernel is more picky about parameters in fstab - invalid parameters seem to prevent the mount instead of just being ignored. Changed the line to '/dev/cdrom /media/cdrom subfs auto,procuid,nosuid,nodev 0 0' and all works fine now. Space is starting to get a bit tighter on the storage volume. I figure sometime in the next 6 months I will have to add more space. I think a 250 GB SATA drive makes sense. I'll need a card for it and I'm still looking for a good one without spending a fortune. Great performance is not a requirement for this - it just needs to be reliable. I'm thinking one of the Silicon Image based cards should do the trick. Since SuSE has announced that support for 9.0 is going to end on Jan 1, 2006 I think it's time to think about upgrading the server before they announce the drop date for 9.1. I've installed SuSE 10.0 on my laptop and desktop machines and there are some issues with packages being dropped that I will have to resolve. Most notably is the absence of clam. It's not a big problem though - go to the clam website and there is a place to download binaries for SuSE (which turns out to be ftp.suse.com), The other missing item I found was ddclient but the rpm from 9.3 installs and runs OK so I'm not worried there either. I kind of understand why they dropped clam as they have something else they're pushing, but not ddclient. Makes no sense to me. I need to search through all the stuff I have installed and make sure it's available on 10.0. |
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May 15, 2006 Well, another long time between updates but not a whole lot happening anyway. I did add a 250 GB drive to the mix and rearranged things quite a bit. I abandoned the SATA route and stuck with good old Parallel ATA. When I opened the machine up I discovered it only had a 250 watt power supply and decided that I should probably put something bigger in. I had a spare around so that one was easily solved. I did check for heating problems and nothing in there was even beyond warm right after shutdown so I don't need to worry about cooling. It's a giant sized tower so there is lots of air space and I had already added a couple of extra fans. I learned a few things when I installed this drive. Most importantly I learned to not mess up the fstab. BAD things happen at boot time if you do - like the boot doesn't continue through. Took me a long time to figure out what had happened as the appropriate message kept scrolling off the top of the screen too quick to catch it. Anyway, in stages I reworked the big drives into a mirrored pair of 20 GB partitions and whatever was left for individual large storage spaces. The new 250 will be used for backup and the old 120 for just "stuff" like suse install disks and the like. It's just a large sharable space. I then moved the /srv/www files over to the "new" mirrored space. It became /msrv/1/www so there were a bunch of things to change. It took me a few days to find them all but everything seems to be OK now. After I found them all I decided that something wouldn't like this when it comes time for updates so I built a symbolic link so you can still see everything like it's still in /srv/www. Today was also the day of the dreaded announcement from SuSE about the end of 9.1. The magic date is June 15th so it's time to get moving and upgrade to 10.0. I know I could just continue to run with it but I should just bite the bullet and do it. I found what happened to some of the packages that were missing. They moved to the source DVD. At least ddclient did. Postgres and clamav are available from ftp.suse.com/pub/projects/ |
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December 7, 2006 Long time again but then not a lot has happened either. I acquired a "better" backup server - it's a Gateway (ugh!) Celeron 533 with 160 MB of RAM. I have SuSE 10.0 loaded and TWO 4 GB hard drives in it so it can fully support all the web page stuff including the Gallery. Had some trouble with cooling - the single fan in the mini sized power supply was the ONLY fan and it was supposed to blow on the CPU heatsink. Worked OK with the cover off but crapped out in short order once I put the cover on. I added a case fan and a deflector to the PS fan to blow air more towards the CPU. Works fine now. Anyway, it's ready to go. I had to do a bit more work on this backup server because I started integrating CGI scripts in some web pages that pick up data from SQL databases so I had to get MySQL set up on this server too. I don't have all the details worked out for syncing the SQL data yet but it should be pretty easy. The data doesn't change that much so a once a day sync should do it. I haven't gotten any updates for the SuSE 9.1 system for a while now and updating is going to have to happen soon. And of course the sellout of SuSE to the evil empire has complicated matters. I'm just not ready to go through a major switch of distros right now even though I have the one I want to use all picked out (I think). I think I'll get it updated to 10.0 which will buy me some time to get the next step figured out. I did some experimentation with CentOS which is based on RedHat Enterprise Server. It looks like the way to go and has some reasonably long support timelines. I've always been uncomfortable with the relatively short ones of SuSE but I really liked how slick and easy things were to install and maintain. Fortunately the RedHat way is somewhat familiar to me so it shouldn't be too bad. I think I'm going to load CentOS on my desktop PC over top of SuSE and see how that goes. That should give me some good experience for the future. I finally got around to updating POPFile to the latest release. I figured this would be a problem since SuSE 9.1 didn't have the latest release of SQLite which the POPFile now needs. It turns out that POPFile can't use the current version (bugs in SQLite) so all was cool. |
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October 17, 2008 OK, a REALLY long time since the last update. I've pretty much decided to leave the server, for now at least, on SuSE 9.1. Everything is pretty stable and works just fine. I can keep Clam antivirus updated manually. I've also done some web development with CGI scripts. What I've done is pretty basic and mostly just functional but it's for my use only so it doesn't really have to look pretty. I've propagated the code and ideas to different databases and some different funtionality. This was all before I recently discovered PHP. I'd been putting off learning yet another scripting language only to discover that it's much easier than learning PERL. In fact, it so closely resembles C that I now realize that I never should have spent time doing CGI scripts. I had the basics down for PHP in just a couple of hours and was writing database applications within four. It's so much easier when the "new" language so closely resembles one you already know. I have one new challenge coming up though. I'm going to be moving one of the web sites to another Linux server and it does include moving a MySQL database with it. I think I have everything figured out so it should go smoothly. I have a couple of months at least so I have time to work out any problems. |
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September 5, 2010 The server is still chugging along but I'm going to have to get more involved keeping Clam updated. I can no longer find a proper RPM for it so I have to build it myself. The first time I did it all went pretty well and I figured I'd wait a few days before actually installing it. The very next day after the build a new release was announced. I skipped that one and waited for the next release and went through the build again. It's probably time to actually install it. I've been looking at CENTOS. I'm liking what I see but haven't had much time to play with it yet. I just got a new (to me anyway) IBM T42 notebook and installed CENTOS 5.5 on it so I could play with it more. I'm usng MySQL more with PHP, particularly with the addition of the trian club web site: http://www.cuyahogavalleyterminal.org. Most of it is hidden from non-members though so you don't really see it. I'm also generating the calendar "offline" but automatically based on MySQL data. |
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