The "Linux questions (and other stuff)" thread

[Speed Daemon]

why would Linux need anti-virus software?

One good reason is because not everyone uses Linux, so being able to scrub out malware in a relatively secure environment is a good practice. Linux powers many file and web servers that Windows and Macintosh computers connect to. I know that I wouldn't want to find out from an irate client that I gave them some malware!

While Linux itself is relatively secure (if you patch it religiously and practice good basic security protocols), there have been some Linux exploits. (The word "virus" is hopelessly out of date.) I'd rather have ClamAV scan my Linux machines' filesystems from time to time just in case.

 

[Speed Daemon]

Let me put it this way--and please keep in mind that I've used *nix since 1985, okay? In *MY* experience, a properly configured, administered, and maintained *nix system will not have any type of security issue, including viruses. For the record, in 28 years, NONE of my UNIX/Linux computers and/or networks has ever been compromised.

By practicing the same basic security protocols on my Windows NT machines, I've never had any of those infected with any malware either. A little common sense can do a lot of good.

 

[saptech]

Also if you're using linux desktop and connecting or trading files with Windows machine, it wouldn't hurt to have an antivirus program installed.

I've never had a virus on my linux machines since the mid 1990s, but I've never had one on my Windows machines either. Well once, my teenage son did get one visiting porn sites. I've never ran a virus scanner on linux but did try ClamAV just to see how it ran.

 

[mikedt]

Clarify . . . are you saying that if I run Linux, there is absolutely no possible way I will suffer a virus?

I took a look and remember, I am not an expert.

Meet Linux Viruses | Unixmen

Most those seem to be experimental or proof of concepts from the late 90s. Or they involve the users doing something, like opening a malicious document, code injection. Hopefully no Linux users are running something like OpenOffice, or internet browser, or IM, or e-mail client with root privileges, e.g. "$ sudo openoffice" Which is something Windows does by default. all software runs with admin/root privileges. Although MS have tried to stop that.

As a teacher in China, I'm always opening potentially malicious and dangerous documents. I'm using Linux, but if LibreOffice or MS Office on Wine, suddenly asked for my root password, because of some document trying to do something to the system. I'd immediately know, something is wrong here.

This why logging in as root is always a bad idea. I've never had to do that. Login as root is sometimes hidden in certain distros, to protect novice users from themselves, and you don't need it anyway.

 

[MoodyBlues]

By practicing the same basic security protocols on my Windows NT machines, I've never had any of those infected with any malware either. A little common sense can do a lot of good.

How does NT compare to *nix in terms of its inherent security, vis-

 

[mikedt]

How does NT compare to *nix in terms of its inherent security, vis-

 

[nickdalzell]

if i double click on a JPG in Ubuntu, it opens up whatever picture viewer is default, just like windows. i don't believe executable exists in Linux--everything is a file!

Now our college used and we were required to have our own version (trial) of WinNT 4 and Win2K and i do know the Guest account cannot even set the system time! much less change sensitive info. a 'user' in Linux (i do not recall there being sub-groups in *nix such as guest, power user, and so on just user and root) has more power. a 'user' can use his own user password (Ubuntu does not set a separate root password in its installer ) to sudo anything. there is no security when a person can simply use a generic user password to gain even temporary root priviledge, which can be dangerous in itself. but i don't see too many Linux users complaining about problems the way Windows does.

 

[mikedt]

if i double click on a JPG in Ubuntu, it opens up whatever picture viewer is default, just like windows. i don't believe executable exists in Linux--everything is a file!

Oh it definitely does. Appications are certainly executable on Linux, e.g. Chrome. Just that they don't usually have any file suffix. .bin might be used sometimes, to indicate a binary/executable file.

Here's the file permissions for a JPG, it's actually my AF avatar. This is on Mint, which is Ubuntu based.

Everyone can open it and look at it, but they can't change or modify it, or change the file permissions. The only users who can do that are "michael" (me) and root. Note that "make the file executable" is unchecked. The OS would never try to run it, even if there was code hidden inside.

Now our college used and we were required to have our own version (trial) of WinNT 4 and Win2K and i do know the Guest account cannot even set the system time! much less change sensitive info. a 'user' in Linux (i do not recall there being sub-groups in *nix such as guest, power user, and so on just user and root) has more power. a 'user' can use his own user password (Ubuntu does not set a separate root password in its installer ) to sudo anything. there is no security when a person can simply use a generic user password to gain even temporary root priviledge, which can be dangerous in itself. but i don't see too many Linux users complaining about problems the way Windows does.

You are the "administrator" for your own system, in the absence of a corporate sysadmin. And so the user password is the sudo and root password for your own system. You can set a seperate, password and admin/root account if you want for Ubuntu. There's nothing stopping you from doing that. Which is what enterprise users would do.

 

[MoodyBlues]

if i double click on a JPG in Ubuntu, it opens up whatever picture viewer is default, just like windows.

That's not what mikedt is referring to. Automatically opening a JPEG in the default image viewer is not the same thing as executing a JPEG. It's the image viewer that's being executed in this scenario, not the image FILE.

i don't believe executable exists in Linux--everything is a file!

Nope! Want a quick, very brief, and not all-inclusive lesson on Linux file attributes?

Every file--and this includes directories, because they're files, too--can have three types of permissions, for three sets of users: read/write/execute for user/group/others. So let's say you have a bash script saved as a file named do_this in your home directory, and its permissions look like this:

-rwxr-xr-x 1 nick users 248600 2013-01-17 22:45 do_this

See the rwx? Those are the permissions for you (user), and they signify read, write, and execute. Then see the two r-xs? Those are for group and others, and they signify read and execute permission only. You can do anything you want to this file, including editing it or deleting it, while everyone else can look at its contents and can execute it, but they can't modify or delete it.

Now our college used and we were required to have our own version (trial) of WinNT 4 and Win2K and i do know the Guest account cannot even set the system time! much less change sensitive info.

Just keep in mind that [just about] anything micro$oft has is [probably] a rip-off, and [usually] a very POOR implementation, of something that originated in *nix.

a 'user' in Linux (i do not recall there being sub-groups in *nix such as guest, power user, and so on just user and root)

*nix has always...always provided for different levels of authority, everything from who could write to tape drives to who could log in only on a terminal and not the server. Again, anything m$ has likely originated in UNIX.

has more power. a 'user' can use his own user password (Ubuntu does not set a separate root password in its installer ) to sudo anything. there is no security when a person can simply use a generic user password to gain even temporary root priviledge, which can be dangerous in itself. but i don't see too many Linux users complaining about problems the way Windows does.

No, that's not how it works. Only a user who has been granted the right to use sudo can use it. Typically, that person would be the one in charge of administering the system.

Ubuntu and its offspring decided that making it harder to enable a true root login would lead to less catastrophe from windows converts. While I certainly see their point, I still think it's a stupid, unnecessary step. As I've said elsewhere, as soon as I install any *buntu or derivative on a new computer, I give root a password AND I enable root logins. I'm a big girl. I don't need hand holding at this point! :laugh:

 

[nickdalzell]

and what if that user tried to use the sudo command and entered his/her own password? same problem

 

[palmtree5]

and what if that user tried to use the sudo command and entered his/her own password? same problem

If they just typed sudo, they would get usage instructions

 

[MoodyBlues]

and what if that user tried to use the sudo command and entered his/her own password? same problem

No, that's not how it works. As I said, a user has to be granted the right to use sudo in order to use it. If they're not in the sudoers file, they can't use the command.

 

[nickdalzell]

BTW Moody how is this thread going to work when it has like three different subjects going at once? how do you sort it in one thread?

 

[saptech]

I'm a big girl. I don't need hand holding at this point! :laugh:

You're a female and know a great deal about Linux??? Wow, I'm in luv!

 

[MoodyBlues]

BTW Moody how is this thread going to work when it has like three different subjects going at once? how do you sort it in one thread?

Good question! Unfortunately, I don't have a good answer. In fact, I don't have ANY answer. I guess people who either have a question about, or think they can answer questions about, Linux will pop in here and see what's up.

 

[saptech]

It is a cli command to backup partitions to another device or partition.

http://www.fsarchiver.org/QuickStart

example command:

fsarchiver savefs /mnt/backup/gentoo-rootfs.fsa /dev/sda1

The example show the command, create a backup using savefs, save it to the destination, and backup source partition.


To restore it I would use a command like this:

fsarchiver restfs /mnt/backup/gentoo-rootfs.fsa id=0,dest=/dev/sda1

What I would like is a script to use it as such:

when I run the script, it will check for an external device and/or a disc in the cd/dvd drive before starting.

the command also can use options if I was to backup to a cd/dvd disc, such as this:

fsarchiver savefs -s 4300 /data/backup-rhel-5.2-fsa033.fsa /dev/sda1

For instance, if the size of your backup is 8GB and you want to save it on DVD+RW discs, it may be useful to split the archive into volumes of 4.3GB.

The -s 4300 is the option for that.

This is basically what I would like. But if you can just get me started on the basic I should be able to add whatever else I may want it to do.

Thnx.

 

[saptech]

BTW Moody how is this thread going to work when it has like three different subjects going at once? how do you sort it in one thread?

Can it be a subfolder under the Lounge folder like the others there? Then when someone have a certain question, they can create a new Thread. Similar to how the Politics, Computer & IT, and the others are designed.

Just a thought!

 

[Prinny]

Posting in this so I can keep up with it on TT

I do have a question though. This is more generic than having to do with bash and whatnot. Well sort of. Anyway!

Source based distros (Gentoo, Sourcery, etc.) Do you think that they are better than distros such as Ubuntu? I understand that Gentoo and the like are not for your average/novice Linux user. I tried Gentoo, and I for the life of me could not get it to work.

Regardless. Which do you think is better for the most part? Or is it one of those "case to case" things?

 

[mikedt]

BTW Moody how is this thread going to work when it has like three different subjects going at once? how do you sort it in one thread?

This why we "quote" whom we're responding to. So everyone can follow a particular subject or conversation. If not, I'd just assume it's a response to the OP, or the post above, or it's just a general comment for the thread. It's something we've always done for usenet and mailing lists, and forums are not really any different.

Your post mentioned Moody, but I felt it needed an answer that I could give.

 

[saptech]

Posting in this so I can keep up with it on TT

I do have a question though. This is more generic than having to do with bash and whatnot. Well sort of. Anyway!

Source based distros (Gentoo, Sourcery, etc.) Do you think that they are better than distros such as Ubuntu? I understand that Gentoo and the like are not for your average/novice Linux user. I tried Gentoo, and I for the life of me could not get it to work.

Regardless. Which do you think is better for the most part? Or is it one of those "case to case" things?

I think Source based distros are relevant to those that only want to install what they need. In a server operation this could work out for the benefit if you need specific compilation on the hardware you're using.

The average users really don't need it, plus with newer hardware may not be worth it.

Sourcemage is my favorite SBD, but I haven't messed with it a couple of years.

 

[MoodyBlues]

You're a female and know a great deal about Linux??? Wow, I'm in luv!

Yep, last time I looked, I was female! :laugh: And I've been a *nix-ster since 1985. I actually switched career paths because of UNIX. Long story, but I needed a break before starting medical school, one thing led to another, and I ended up in a created-just-for-me position at the furniture store chain where I worked [doing data entry] while in college. I transitioned them off their IBM System/3s, creating a multi-location and, of course, multi-user UNIX system. I did everything--installing hardware, administering the system, programming, all of it. That was my favorite job ever.

I occasionally ruminate over the fact that I always intended to be a physician, and I essentially blew 5 years of hard work [A student, with honors] in pre-med, but for the most part I'm fine with it. When something comes up, like the brain tumor I had, I do find myself wishing I had gone on with med school so I could be more involved in my care, but those thoughts are few and far between.

 

[nickdalzell]

i started when i was in college, heard about this 'Free' OS for awhile and found linux.org (site seems to have changed owners and looks completely different now) and downloaded Basiclinux, my first distro--had to compile everything. X windows actually booting up without a WM or DE was at the time something to be proud of at least for me, and using the links browser in frame buffer graphics mode was a feat in engineering in BL. but unfortunately it was not ready to replace Windows. that did not end up happening 100% until a few days ago. but i did distro hop in and out of Windows space a bit, i bought the complete Red Hat 7 set, six discs with a couple for source code, every app that was available in the repos at time of release. wow. but eventually Netscape couldn't keep up so back to Windows i went. also, RH 7 wouldn't run Bearshare--it would load the app but it would not connect. and that was a heavy used app at the time. also, my CD Burner refused to play nice with the old software it had. suddenly having every app released at the time of the disc set was not as impressive as it was when i bought it. i later burned the first Ubuntu, of course being stupid, as a deer lover myself i liked the name Feisty Fawn. but it really had zero support for a very used Compaq 1200 series. no support for PCMCIA, USB wifi, or anything i used. but it did have sound and the video going. but without internet was essentially useless. back to Windows. then came Mandriva. hard disc decided to go into an infinite activity loop and the distro refused to boot, couldn't fsck either as it woule auto reboot when entering root password. back to Windows. well you can see what ended up happening by my past threads here.

 

[argedion]

recently working on a project that called to find out if a file existed or not I had no idea of how to do this in Linux. Not being always the sharpest tool in the shed I tried several ways and failed miserably. I searched a little but since I suck at searching (never know really what to ask) somehow though i seemed to have found my way and its really simple.

here is a test condition to find if a file exist or not using bash

if [[ -e "filename" ]] ; then
true
else
false
fi

just thought I would share for those who didn't know

 

[nickdalzell]

there is also the 'whereis' command that is a lot less complicated:

$>whereis startx

bash: /usr/X11/startx

if the file did not exist it would be like:

$>whereis foo

bash: no such file or directory

 

[MoodyBlues]

recently working on a project that called to find out if a file existed or not I had no idea of how to do this in Linux. Not being always the sharpest tool in the shed I tried several ways and failed miserably. I searched a little but since I suck at searching (never know really what to ask) somehow though i seemed to have found my way and its really simple.

here is a test condition to find if a file exist or not using bash

if [[ -e "filename" ]] ; then
true
else
false
fi

just thought I would share for those who didn't know

Is it okay if I post the contents of your PM here? Do you even still need help with it? Putting it here will benefit others, too, plus someone besides me can chime in!