The Linux Help and Tutorial Thread

[PoppaGeek]

How to create and edit files using the GEdit Text Editor. This is like Windows Notepad and just as simple. I will use the BoincTasks config files gui_rpc_auth.cfg and remote_hosts.cfg as examples.

Applications > Accessories > Terminal When terminal opens type the following then hit enter: sudo /usr/bin/gedit Enter your password. gedit should now be open.

For Boinc installed from the command line using apt-get:
Click on Open then in the left column click on File System on right column double click on etc scroll down to boinc-client and double click.

For Boinc installed from download:
Click on Open then in the left column click on File System on right column double click on home scroll down to your login name and double click and double click on BOINC.

For Dotsch Boinc/Linux installs:
Click on Open then in the left column click on File System on right column double click on home scroll down to boinc and double click and double click on BOINC.

If Boinc was installed another way just replace the directory names above with the location your config files are in.

If you are in the correct directory now, depending on the way Boinc was installed, you should see gui_rpc_auth.cfg in the right column. Double click on gui_rpc_auth.cfg. On my install the file is empty. If there is anything shown in the window delete it all using the Backspace or Delete keys. Now click on Save. Now File > Close.

Now click on File > Open or the Open Icon. Double click on remote_hosts.cfg. If remote_hosts.cfg is not listed then click on Cancel at bottom right corner. Then click on File > New.
Go to the end of the file and type in the IP number of the machine that BoincTasks is running on. It should be something like 192.168.1.100 or 10.10.10.100
now save and close. You can restart Boinc or reboot the machine. BoincTask should see your Linux cruncher now.

[D_A]

I don't know if this works on other distros but in Ubuntu you can avoid having to click through menus to open things as root by clicking ALT+F2 and then entering gksu <application name> in the window that pops up. eg gksu gedit will open gedit as root wihout having a terminal open as well, unless you click the checkbox to make it do so.
You can run any application you like from this window, the "gksu" part just makes sure it runs with root privileges. For some reason "sudo" doesn't always work with this which is why I use "gksu".

[trn]

Ooo! Ooo!

Here's a handy little thing:

find - finds files and directories on a linux system

eg

find / -name boinc-client

the form is: the command, then the starting directory (the search starts here and can go deeper but not above this directory. can be anything, in this case the search would start in the root directory), the -name signifies that the thing it's looking for is named "boinc-client"

The command is actually FAR more powerful than this example shows, but that's what man pages are for

Some distros name the boinc-client folder 'boinc' also. /var/lib/boinc

ps -aux (console command to show all processes running, handy to check processor usage without a system monitor or desktop manager or GUI.)

ls -l (-l is the flag for viewing file premissions with the ls command, -a is the flag for show all.)


And the most handy advise that D_A gave me for a dedicated cruncher running linux. To admin boinc edit your gui_rpc_auth.cfg and remote_hosts.cfg files (as if you were setting up boinc view.) And then just use the boincmanager to connect to the linux client and you can admin boinc. This is much easier than messing around with X and gui's or vnc or anything else. I don't even install X or a dm on my linux crunchers. Package management of a distro + boincmanager and your good to go

[nanoprobe]

Many thanks to PoppaGeek. He was able to help set up Boinctasks to view my Linux crunchers from the Windows host. I vote for sticky for this thread.

EDIT: Added proof

[D_A]

Speaking of sensors, I do have another (much less urgent) question maybe you guys might be able to help with. Are any of you guys running linux on an AMD system? My PII 1055t box is running Ubuntu 10.10 (which has k10temp support in the kernel), but the sensors applet shows a completely different CPU temperature than what's indicated in BIOS - about 19C cooler. The applet allows for both additive and multiplicative adjustments to the value displayed, so I simply added 19 to the temperature value at idle. Is this correct, or is it more complicated than that? The machine's been running for several days now with no hiccups, so I'm not real concerned about this one.

I think we missed this one.

With the Hardware Sensors applet in Ubuntu you really need to look through all the available sensors as it doesn't always automatically pick the best ones. Also remember when doing reading comparisons that when you're in the BIOS, WCG isn't running and neither is anything else so the CPU really is as completely idle as it can get.

[dangaroos]

when troubleshooting i frequently timestamp vmstat and log it to a file using this command :

vmstat 1 | awk '{now=strftime("%Y-%m-%d %T "); print now $0}' |tee -a somefile.txt

it is probably dependant on gawk for strftime function, i remember getting a error saying "strftime not found". If that happens on Ubuntu install gawk using (should also be ok to replace awk in the command with gawk) :

sudo apt-get install gawk

I use it for those "what was the cpu/mem/io/swap status on the machine yesterday at 4.00am" moments.


If you want this to run forever and are using a remote ssh session put a "nohup" at the front and "&" at the end so the logging will continue after you close the remote ssh session. To stop it you will need to do a ps -ef and find the process id (PID) and use kill.


It will only update the screen after writing X (25 ?) number of lines.

D

[Gamekiller]

Thanks for this thread guys! It helped me get through a few confusing spots while getting my linux server up!

Thankkksss!!

[PoppaGeek]

Glad we are able to help. Please post whatever problems you are running into so we know what will be useful.

[PoppaGeek]

Added directory navigation and identification commands to first post. cd and pwd


The command to delete a file is rm. There is no undelete. If you have a file named test in your home directory and you type rm test it is gone. Period. Unless there is an important reason to permanently delete the file just rename it using the mv command.

To rename file test.cfg to test.cfg.backup
mv test.cfg test.cfg.backup

[SMTB1963]

Added directory navigation and identification commands to first post. cd and pwd

---

First, a request - would it be possible to consolidate all the info in this thread into the first post? I'm finding myself referring to it more & more often, and...well I'm lazy and don't want to have to re-read through everything. Plus, I'm old and infirmed:





Now a question - I've had 3 of my PCs plugged in and running around my workspace in order to set them up for this week's activities. Well, the kids from across the street came over Saturday and were playing games on my main system, which caused the breaker to trip (should'a seen THAT coming). Everything started back up fine, but last night and again this morning I've noticed that one of the linux boxes has been freezing up intermittently.

I suspect it's a disk issue, so my question is how do I go about running a "CHKDSK" - like program to find/fix errors and mark bad blocks? I saw some stuff on the interwebz about "fschk" and "badblocks", but I thought I'd ask here rather than spend a bunch of time researching this just to end up going down the wrong path. (happens to me alot)

Oh, and if anyone thinks it might be something other than bad disk/data, feel free to point me in the right direction.

Thanks again to all the linux gurus for posting here so the rest of us can get up to speed.

[D_A]

From an Ubuntu perspective:

There's a few different ways to do this, but this is the one that I have most luck with. Open a terminal and type

 sudo touch /forcefsck

and then reboot the system.

The program you use that's like chkdsk is e2fsck. It has a ton of options but in order to actually check the disk it needs it to be unmounted or it can hose the file system, which it will warn you of if you try to do it manually. Doing it this way, the disk is checked and cleaned before it is mounted at boot.

[Gamekiller]

Running Ubuntu 10.10 (regular version I guess).

I'm trying to set up a raid 1 array. I'm not booting off of it. It's just for file storage (media) and I'll have samba and ushare pointing to it. I set up my raid in the bios on my Gigabyte GA-MA790X-UD4P and booted into Ubuntu. I see both disks marked as 1.0TB RAID Component (in volumes box) under SATA Host Adapter and I also see "1000 GB Hard Disk" that reads "Free" in the volumes box. I assumed the last disk I saw at the bottom was the two disks combined in raid and tried to create a partition but it wouldn't let me so I figured I should look up some info. All I can find is guides for booting from a raid.

Some things I read said I need to use the server install of Ubuntu instead... which isn't an option I want to take seeing as I have my current install set up like I want it with boinc/gkrmellm/minecraftserver/ yadda yadda. lol
So this would be a "fakeRaid" and not a "softraid" because I turned it on in my mobo's bios right? I grabbed dmraid (and libdmraid 1.0.0.rc16) from the package manager thinking it's what I need and that I could figure it out... until I read the README and I'm not sure I want to tackle that option unless it's absolutism what I need.

Anyways, I'm going to need some help here please... with Ubuntu and my overloaded brain! Thanks!

[D_A]

I'm afraid I've never set up a raid array (never had multiple drives for one machine to play with like that) so I can't really help much.

[PoppaGeek]

Sorry never did any raid under Linux. No idea where to even begin. I'd say if you are determined to do so ya got alot of reading to do.

[D_A]

I'll hazard a guess and suggest that you'd want to set things up as hardware raid. Linux SHOULD see it as just a thumping big hard drive while all the fun stuff is handled by the hardware controller.
No I don't know how to do that either, it's just a thought.

[Gamekiller]

I'm still working on it. Read somewhere that "softRAID" is better supported than "fakeRAID" so I'm trying that out at the moment. (softraid is software only, fakeraid is the mobo/cheap raid card pretending to raid/ and realraid is using an expensive raid card that does the work--- the terms are new to me)

Linux saw two physical drives and one logical one or something along those lines when I was using the bios to raid. Though, it wouldn't have anything to do with them even if I begged. lol

So where as I was doing fakeRAID by telling the bios to do it, now I'm attempting to let Ubuntu have at it solo.

I'll post what I find. (so fun!)

[Gamekiller]

Not sure why something so simple was so hard to find....
http://en.wikipedia.org/wiki/Mdadm
Bam... took less than 5 seconds..
It's resyncing atm, two blank drives but still going to take hours for some reason. Hopefully after the resync it works.

Now I need to learn to program so I can make a GUI for all of the commands to keep up with the array.

[SMTB1963]

From an Ubuntu perspective:

There's a few different ways to do this, but this is the one that I have most luck with. Open a terminal and type

 sudo touch /forcefsck

and then reboot the system.

The program you use that's like chkdsk is e2fsck. It has a ton of options but in order to actually check the disk it needs it to be unmounted or it can hose the file system, which it will warn you of if you try to do it manually. Doing it this way, the disk is checked and cleaned before it is mounted at boot.

Thanks!

It ran when I re-booted, but there wasn't any feedback on the results. I checked the log files in /var/log/fsck, but they just said "(Nothing has been logged yet.)". Does this mean it ran successfully with no errors/fixes, or is there another log file somewhere with the results of the scan?

[josh1980]

Honestly, I can see this thread could get to be quite long. It would be very cool if someone could put together a .pdf or word file or something that could include all of the info collected in this thread and keep it in the first post (poppageek). I'd offer to help with maintaining the .pdf or word file if we do want to go that route. The experience would be good for me since I'm trying to get into Linux myself. We could give it a name like "Xtremesystems Linux WCG Noob Manual" or something.

I'd love to hear this answer from someone that works at Intel and could give us some inside knowledge or more detail(or maybe correct me if I am wrong).

[D_A]

Thanks!

It ran when I re-booted, but there wasn't any feedback on the results. I checked the log files in /var/log/fsck, but they just said "(Nothing has been logged yet.)". Does this mean it ran successfully with no errors/fixes, or is there another log file somewhere with the results of the scan?

That's the only one I'm aware of, so I'd assume it means everything was ok.

[PoppaGeek]

Honestly, I can see this thread could get to be quite long. It would be very cool if someone could put together a .pdf or word file or something that could include all of the info collected in this thread and keep it in the first post (poppageek). I'd offer to help with maintaining the .pdf or word file if we do want to go that route. The experience would be good for me since I'm trying to get into Linux myself. We could give it a name like "Xtremesystems Linux WCG Noob Manual" or something.

I'd love to hear this answer from someone that works at Intel and could give us some inside knowledge or more detail(or maybe correct me if I am wrong).

I am thinking maybe a google.docs link might work but one of my concerns is it all getting overwhelming for someone. Many people never try or get very far with Linux because there is so much there, at the command line anyway. What I was trying to do was just enough to setup and run a cruncher under Linux. There are a lot of web sites that have good FAQs and HOWTOs to all this and much more. Yet people still do not use Linux for a cruncher.

So I am trying to keep it from becoming overwhelming and yet still have what people need. The way I see if is if something gets asked then it may need to be added. If not then why do it? No sense in adding disk trouble shooting or raid arrays to the basic parts of it. In other words I think we need to keep some simple and just enough and still be able to answer the more uncommon problems.

Thoughts?

[D_A]

I agree. We're not trying to train people to become l33t kernel hackers here. This is really to get people comfortable with the basics and provide a place to ask questions about things as they come up.

[SMTB1963]

That's the only one I'm aware of, so I'd assume it means everything was ok.

Well, so far so good - 36hrs+ with no lockups on that box. Thanks again!

I am thinking maybe a google.docs link might work but one of my concerns is it all getting overwhelming for someone. Many people never try or get very far with Linux because there is so much there, at the command line anyway. What I was trying to do was just enough to setup and run a cruncher under Linux. There are a lot of web sites that have good FAQs and HOWTOs to all this and much more. Yet people still do not use Linux for a cruncher.

So I am trying to keep it from becoming overwhelming and yet still have what people need. The way I see if is if something gets asked then it may need to be added. If not then why do it? No sense in adding disk trouble shooting or raid arrays to the basic parts of it. In other words I think we need to keep some simple and just enough and still be able to answer the more uncommon problems.

Thoughts?

Yeah, I see your point (reluctantly). No need to re-write the man pages.

I honestly don't understand why linux isn't in wider use. I've only used Ubuntu, but it's been a relatively smooth experience so far. Stability, security, and oh yeah, it's FREE.

[OldChap]

I guess it is fair to say that that is exactly what I will want from Linux in the first instance...

Crunching (and maybe MJ 12 ) up and stable and free

The next step is to get to grips with Wine for folding GPU and then, and only then, will I consider any other features in order to use as a daily setup.

Perhaps more simply put any step by step Linux crunching tips get my vote.

[D_A]

I honestly don't understand why linux isn't in wider use. I've only used Ubuntu, but it's been a relatively smooth experience so far. Stability, security, and oh yeah, it's FREE.

That in itself is a long and convoluted story with Corporate interests working against it on one side and all manner of people and positions on the other. Add to that the various patent trolls and convoluted really doesn't even begin to cover it.