Linux steep learning curve

Hey guys. I've been a microsoft goon for a long time. I've been doing system admin/troubleshooting stuff for about 10 years, and getting paid pretty well for it. I kind of pride myself on being a fairly clueful person, I've pulled of tricks that should not have worked, supported tons of production machines and kept uptime on critical boxes high, etc. I'm entirely self taught and have managed to learn SQL, Exchange, server, and a ton of apps.

My problem is, at my current client, they are uh, shall we say, cheap. They need a cache/proxy service to help 'speed up' web traffic. I know squid does a good job, and so I threw together some parts and did a network install of redhat 9. Easy enough.

My problem is, redhat installed squid, but it doesnt seem to be running. I tried to install webmin with an RPM and I double click on it, it hops from 1/3 to 1/2 done and then the window goes away. So I downloaded a new build, managed to do the make and whatevers and install the new build of squid. It still doesnt seem to be running.

The interface in redhat (I think Im using xwindows and gnome, not really sure) is not intuitive at all. The advantage of microsoft products is that you can depend on things being fairly similar, or at least make certain assumptions about how to manage services, settings, etc. I read that the squid process has to have rights to the cache directory, ok great, how do I do that? what is the squid process? Is there some shell I can load on redhat to give me links to things like this? Am I dead in the water? Do I need to go buy some "how to admin linux" books to do this? I've honestly never had to read a book on any piece of computer technology before? Checkpoint firewall? No problem, dorking around with the gui and phone-boys site was enough. Exchange 2000/Active directory migrations? No problem, read 2 paragraphs in a white paper and messed around on the home machines for a few days and had it down.

I was hoping for something similar with linux, but after having this machine running for a week, I can't even be sure squid is installed correctly, or running. If it isn't running, I have no idea why not. I have modified the config file and it makes pretty striaght forward sense.

What gives? Any "Windows 2000 Server" shell I can put on red hat to have it make sense?

You sound like me when I started using Linux a year or so ago.

http://www.linuxhelp.net/guides/squid/

Try this tut out and see if it helps. Keep googling and finding tuts and go over the man pages until you get it working. If you give up, you'll never know how it works.

Good Luck.

Wow! Thats a good tutorial. I'll run thought it and see what happens. Thanks a bunch!

A good place to start is in the squid.conf file(usually in /etc or etc/squid). I'm sure the tutorial link posted will explain in detail.


-Maestr0

Thats kind of true. The conf file is good at explaining the settings for squid, but doesn't do anything to explain how to make sure its running, etc. For some reason when I installed, QUICKSTART wasn't placed in the etc directory either, although the faq on squid-cache clearly said it would be there.

I would recommend getting the Red Hat Linux 9 Bible. I've read it myself. It's not my first linux book, but I consider a great reference and how-to book. It really walks you though to doing everything you want to do.

Trust me, it's a great book, it comes with the distribution, and you'll learn to help your clients much better.


--PuRe

to find out if a process is running, you can use the ps command.

ps -aux | grep squid

should tell you if it is running

you can use the man pages for any commands you are not familiar with.

man ps

will list the manual for that command

man grep

will list the manual for that command

a lot of times you can put a --help after a command too, to get a short list of the flags.

Oh, and I agree with PuRe. The Red Hat Linux Bible 9 is a great book. I have this and it is a very easy to understand book. Especially for beginners.

So I'm really going to have to read? I know, I know, I sound like I'm whining. I was hoping this would be user friendly enough to pick up is all.

Ok, I'll check out the bible, thanks for the advice.

Just a quick FYI:

If you didn't already know... you can find just about anything you want using googles linux search

Googles Linux Search Page

Some other useful links:
The linux documetation project
Single list of how-tos

Looking for a specific app to do the job but don't know what its called?

http://freshmeat.net/
http://sourceforge.net/

Looking for a specific RPM but can't find it? I know... you can alway compile... but RPM is much easier IMO.

http://rpmfind.net/

Besides those... the bible is a great resource.

You can also join a LUG (linux users group)

Find one near you and join. Most of them hold regular meetings... where you can meet other geeks interested in linux just as much as you are. I'm a member of a LUG at a local college near me... those guys know it all. One email will return dozens of replies... all with several ways to accomplish something... or advise on how to fix a problem you are having.

jeffs72, I think that your problem with linux is one of its greatest security advantages. Linux is not the sterotypical norm for script kiddies. Think about it. Just about everything in the microsoft world is accomplished through a simple Graphical Interface, it is simple for some 12 year old sitting at home to scan a network and find a system running a trojan wich lets them control the system as if they were sitting in front of the machine. How many computers out there do you think are running PC anywhere with out passwords enabled, way to many. With Linux on the other hand it takes some knoweledge to configure and destroy things. True linux gui controls are becoming more and more popular with the latest distros, but things are still not in the same place that normal Microsoft users would be accustomed to looking for them. I have had friends over who think they know so much about computers, I let them sit at my system and they are dumb founded. Not that it is difficult to use, but they are in shcok that there is something other than Microsoft.

With a little time, and effort, and yes even reading, Linux is more then easy to comprehend. I hope that you find as much excitement and facination in learning Linux as I did. Have fun.

DeafLamb

Boot in text mode then graphical, do this by: typing linux text I installed linux ass backwards did graphical mode first set partitions using LILO got done installing it restarted system, gave me a prompt for the Username root
password ***********

error 319 %^$^^% $#### @@@@@@@@@@@@@@@@@@@@@@@@@@@@@99 some type of bufferoverflow had to unistall and load linux from text mode first :)<--

I have been a busy redhat nut updating distros as they come, i found redhat 9.0 to be very buggy (it still needs work) i eyed off mandrake 9.2 suggest you try that!it has the latest gear.

Damn, if you can read 2 paragraphs in a white paper and have it down, you’re a better man then me.

Although many things can now be done in a GUI on Linux, the question is do you really want to?
You said a client wants a proxy server to “speed things up”.
What types of “things”?
More important, what type of client?
What are their security needs ?

Another thing bothered me about your post. Why would you be installing the RPM and then doing “the make and whatevers” ? Did you uninstall the original first? Did you install any updates from RedHat ? Do you know what an RPM is or how it works ?

If it is going to be a production machine you should learn to use the command line, and NOT install a GUI unless it is necessary. The more services you have running ( including X and Gnome ), the more holes that are possible. ( remember, this is a security site )

You should NEVER, NEVER, NEVER just slap together a machine with default settings out of the box ( not Linux, not BSD, and not Windows as you should already know ) and place it in a production environment just because it works.

In the environment envisioned, will it be necessary to CHROOT Squid ? ( I would regardless )

Yes, you are going to have to read. Yes, it is going to be work on your part. Although RedHat 9 is much better then say RedHat 5 at default settings for security, for a production machine you still may have to tweak things, and you are definitely going to have to know what to install and what not to install.

If you are as good at M$ products as you think you are, then what I have said should be no surprise. Otherwise I think maybe you should go back and read more then just 2 paragraphs of the white papers you perused. And definitely read more about Linux before offering it to a client.
phishphreek80 had some great starting links.

IMHO.
But what do I know?
IKnowNot

I know Linux junkies will hate me for this....But KDE has a nice Windows knockoff of ADD/REMOVE programs, try installing the Squid package through there. I had that problem with VNC not installing correctly, and ran it through the ADD/REMOVE, and it worked perfectly.
GNOME might have this option to, however I'm not too sure.

well man it is jsut coz ur used to M$..... that is all linux is userfrendly... :D

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Originally posted here by IKnowNot

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Although many things can now be done in a GUI on Linux, the question is do you really want to?

I have heard that running anything other than the command line in linux chews up resources, and I've found this first hand. My hope is to get everything setup, and then disable the GUI, take away the keyboard and mouse, and just access the box via ssh.

You said a client wants a proxy server to “speed things up”.
What types of “things”?

Well, the internet, in vague terms. I report to one of the owners that can spare about 4 hours a month to interact with me, so I'm kind of on a long leash here. I am mainly hoping to use squid to speed up web browsing (a lot of http traffic here, and it's actually business traffic). I'm fairly sure the data T is maxed out, so I wanted to reduce bandwidth usage by cacheing frequently used images.

More important, what type of client?

Not sure exactly what you want here. My client is a mortgage company that doesn't have an IT budget. The clients are win95/98/ME/2000/XP (plus this 'new' redhat box).

What are their security needs ?

Sadly, I'm still trying to sell management on the idea of all users having their own passwords and enforcing a screen saver password policy. Any user control is difficult here, so I try to do a best effort in other areas. All the boxes are patched with SUS, I monitor firewall and switch syslogs, have a strong firewall policy in place, and try to fight people who insist on needing to run p2p stuff inside the network.

Another thing bothered me about your post. Why would you be installing the RPM and then doing “the make and whatevers” ? Did you uninstall the original first? Did you install any updates from RedHat ? Do you know what an RPM is or how it works ?

To clarify, I first tried to install the RPM, which failed at the half way point with no results. So, I downloaded the newest STABLE from the squid server and compiled, etc. Redhat comes with a nifty 'linux updater' much like microsoft, and it's as patched as it can be via that. I'm not sure how to be notified of any bugs/problems beyond that. I am subscribed to thier list, but it only notifies me of new downloads that are available (or seems to anyway).

I THOUGHT I knew what an RPM was and what it did, but since it didnt seem to work... :)

If it is going to be a production machine you should learn to use the command line, and NOT install a GUI unless it is necessary. The more services you have running ( including X and Gnome ), the more holes that are possible. ( remember, this is a security site )

True dat. As I said, the long term goal is to lockdown the box after I figure out how everything works. Like I don't leave services running on my servers that aren't used, I plan on removing/uninstalling/neutering anything not necessary to the function of a caching proxy server. I MAY, if time allows, frag the box and rebuild from scratch after I've climbed the learning curve.

You should NEVER, NEVER, NEVER just slap together a machine with default settings out of the box ( not Linux, not BSD, and not Windows as you should already know ) and place it in a production environment just because it works.

Yeah. Right now I'm testing squid with my machine. I won't move it into production without doing a lock down on it.

In the environment envisioned, will it be necessary to CHROOT Squid ? ( I would regardless )

I fear my ignorance will show through here, but here goes... What's CHROOT mean? If squid is invoked from/as root it starts up and changes itself to the nobody/nogroup setting or whatever. I actually created a user/group for squid that only has permissions where needed (according to the squid faq anyway).

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Yes, you are going to have to read. Yes, it is going to be work on your part. Although RedHat 9 is much better then say RedHat 5 at default settings for security, for a production machine you still may have to tweak things, and you are definitely going to have to know what to install and what not to install.

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Well, so far I've gotten redhat up, patched, and squid actually installed and working. I even went in and got redhat to autorun it at system boot. I am finding that a lot of the meat and potatoes of sys admining a linux box seem to only be accessible at the command prompt. I guess this makes sense considering it's roots. I was just hoping someone somewhere might have made a 'server manager' gui by now is all.

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If you are as good at M$ products as you think you are, then what I have said should be no surprise. Otherwise I think maybe you should go back and read more then just 2 paragraphs of the white papers you perused. And definitely read more about Linux before offering it to a client.

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Gees, that kind of stings. I've plenty of experience with running/building production environments. I've worked for several .coms and other more serious companies, I'm at the point where I can pimp myself out to people through my own company and do well at it. I wish every client had the resources available to do things the 'right way', but not everyone cares about security sadly. I watch Antionline and a few others to stay current, but most small and medium businesses have to have an incident for them to see the light where security is concerned.

My current client dictates my available resources (time to spend on X project, resources available to me, etc). While I'd prefer to do this in a much different fashion, sometimes you have to make some compromises based on the reality of the situation at hand.


phishphreek80 had some great starting links.

Thanks for that link, and I appreciate the feedback as well. This thread has helped quite a bit. I've found several good linux starter resources that I think would have taken me a bit of time to locate. It's always easy to find info on the net, just not easy to find GOOD info all the time.

Quote:

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Originally posted here by disc0rd
I know Linux junkies will hate me for this....But KDE has a nice Windows knockoff of ADD/REMOVE programs, try installing the Squid package through there. I had that problem with VNC not installing correctly, and ran it through the ADD/REMOVE, and it worked perfectly.
GNOME might have this option to, however I'm not too sure.

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Oh wow, awesome. I haven't had time to play with KDE yet. I guess gnome is the default in redhat, and choice isn't as, uh, important to me as most linux people, I guess. I'll poke around KDE and see whats different.

Thanks!

My 1,070th post:

Ok, learning Linux to me is a good idea. After you have it down pretty well, it's POSIX compliant so using another UNIX based OS is usually pretty easy to do.

I made a list of the OSs I own:

My OSs:

1. PC-DOS 6.3

2. BeOS pro 5.0

3. Turbo Linux Workstation 4.0

4. Redhat Linux 6.1

5. Redhat Linux 7.2

6. Redhat Linux 8.0

7. Redhat Linux 9.0

8. Slackware Linux 3.6

9. Slackware Linux 8.1

10. Slackware Linux 9.0

11. Slackware Linux 9.1

12. Open Linux 1.3

13. Caldera Linux 2.2

14. Debian Linux 3.0R1

15. Mandrake Linux 7.1

16. Mandrake Linux 9.1

17. Turbo Linux x.x

18. SuSE Linux 8.1 Professional

19. SuSE Linux 8.2 Professional

20. Free BSD 2.2

21. Free BSD 4.0 Power Pack

22. Free BSD 4.7

23. Free BSD 5.0

24. Free BSD 5.1

25. Windows 3.11

26. Windows 95

27 Windows 95 2nd release

28. Windows 98

29. Windows 98 SE

30. Windows ME

31. Windows 2000 pro.

32. Windows XP home

33. Windows XP home SP1.

34. Windows server 2003

I know it's shocking but I'v only downloaded about 5 of these, the rest were bought and paid for.

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Oh wow, awesome. I haven't had time to play with KDE yet. I guess gnome is the default in redhat

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True, it is the default in rh. Some people have some fierce allegience to one or the other, but both will allow you to accomplish what you want to.
As far as the resources being chewed up, it depends on how good the box is that you are using. If it is a minimalist-type box, then yeah, you will notice a difference. But if it is a P3 or better with 256 MB of ram, I doubt you will see a lot of difference if squid is all you are running it with. Of course, I don't know how much squid needs but you can get a print to screen of all running processes and how much processor and memory they are using with the command top .

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I fear my ignorance will show through here, but here goes... What's CHROOT mean? If squid is invoked from/as root it starts up and changes itself to the nobody/nogroup setting or whatever. I actually created a user/group for squid that only has permissions where needed (according to the squid faq anyway).

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Again, I don't know any of squid, but it is changing itself probably cause it is running as a system process or daemon. Also, CHROOT means to actually change the files that the process recognizes. In linux, the root filesystem (/) is analogous to C:. It is the base folder, the top of the heirarchy. When you invoke the chroot command properly, you can limit the processes's ability to do damage in a worst case scenario by making it think that it is running in the root directory; like nothing else is there above it. Read up on it and do it properly, though, or you cold leave a nice hole.
Hope some of this helps.

Quote:

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Originally posted here by KeyserSoze

Again, I don't know any of squid, but it is changing itself probably cause it is running as a system process or daemon. Also, CHROOT means to actually change the files that the process recognizes. In linux, the root filesystem (/) is analogous to C:. It is the base folder, the top of the heirarchy. When you invoke the chroot command properly, you can limit the processes's ability to do damage in a worst case scenario by making it think that it is running in the root directory; like nothing else is there above it. Read up on it and do it properly, though, or you cold leave a nice hole.
Hope some of this helps. [/B]

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Ah this is interesting. I'll have to read up on it next week. My client is moving offices tomorrow, so right now I'm making sure we don't get screwed by bell south on our T1 installations. :rolleyes:

Thanks!

I am glad to see you got it up and running, and glad to see that a slight setback such as this only encourages you more.

As far as CHROOT goes, I think KeyserSoze covered that nicely. It is usually thought of for things like BIND, and Apache but can be used for other services as well.

I imagine you figured out what your problem was, if not maybe this will help for the future.

If you are doing a new install you can choose the packages to be installed beforehand.

If the system is installed and you want to add something ( in RH 9 w/default GUI ) you can just point to the "Main Menu" / "System Settings" / "Add/Remove Applications". This will bring up a similar window as when installing the system.

The nice thing about the above methods is they will search for dependencies and install them if necessary. RPM is not just a compression program but a package manager.

But just clicking on an RPM to install it it may fail if it can't find the files it needs.

If installing an RPM from the command line, with the rpm file in the current directory
rpm -ivh --test some.rpm

will let you know if there are any missing dependencies ( although in this case "libgd" is actually the "gd-1.8.4-11" package, sometimes the naming can be a little confusing.)

I think you'll have fun learning Linux. Good Luck.

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Ok, learning Linux to me is a good idea. After you have it down pretty well, it's POSIX compliant so using another UNIX based OS is usually pretty easy to do.

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Linux is not Posix compliant. A _few_ parts of it are, but last I checked the Windows 2000 Posix subsystem were more Posix.1 compliant than Linux. (Posix.1e springs to mind)

I believe the only Posix certified OS is still AIX, others just have bits and pieces. Also keep in mind that Posix is primarily focused toward standardized programming for the system (which well all know how well Linux software runs on FreeBSD and how well FreeBSD software runs on HP-UX and how well HP-UX software runs on Linux, etc, etc) so from an administration view point this is of little impact.

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I have heard that running anything other than the command line in linux chews up resources, and I've found this first hand. My hope is to get everything setup, and then disable the GUI, take away the keyboard and mouse, and just access the box via ssh.

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True, but SSHD uses more resources than a local users as well. ;)

On a more serious note, I think for a new Linux user in a production environment, leaving a gui and the local hardware UI intact is a good idea. Despite whatever elitists like to say, the gui is a more productive interface and is likely to save you _significant_ time in the event that anything breaks. This is at virtually no cost to the system as the gui only uses resources when it is running and when it is running will be times when you are fixing stuff, so it is unlikely the computer will be in use otherwise then anyhow. Following this advice until you are more familair with the system will save you many headaches and much downtime.

catch

http://www.antionline.com/showthread...803#post674045 is my previous post on this tread.

" This post shows a clear lack of security understanind. Search on Linux or Windows + ISO 15408 and forget about its "greatest security" advantage of being different than Windows." is the comment I recived with my negative anti-points from catch.

Catch if you noticed I did nost say that Linux Is more secure because it is dffrent from windows. I said I think it is an advantage. Notice the key words in that post. "I think" Therefore it is my opinion and should be taken in context with the rest of the post, along with my user rating and member status. I think personally it is wrong for you to assign me negative points for an opinion. If I purposely gave mis-information it would be one thing. Or if i clearly stated one thing with out checking proper sources, or plagerizing from sources would all warrent negative points. But I did not do any of these things, I gave my opinion. I did however search your quote as recomended and found some interesting reading, thank you for that. But next time post a quote as say that you disagree, don't give neagative points for an opinion.

DeafLamb

"I think that your problem with linux is one of its greatest security advantages"

Indicates that you are guessing Linux's greatest security advantage is what is tripping him not. Not the expression of an opinion as to what is its greatest security advantage. that part was stated matter-of-factly.

I did not flame or berate you, I merely assigned you negative points for making a very incorrect statement about what is a security advantage. I was then kind enough to point you in the right direction for learning about the quantification of systems security.

Isn't there a FAQ somewhere that mentions bitching about AP assignments? You can see how frequently I give negs, so I must have felt your comment was pretty far off.

catch

I have read the FAQ'S and I don't consider my statement bitching.
Have a nice day.

DeafLamb