When i do the following with logged in with root:
Code:
i get
Code:
When i login with user1 and do ulimit -a
i get
Code:
Why is the max user processes different for the same user? And how can i change this. I need for this user more then 20 processes...
I am studying for the LPIC-1 exam, and reading a book that they recommend: "Introduction to Linux: A Hands-on Guide", by Machtelt Garrels. There's one question on the 4th chapter (Processes), that I found confusing: Question: Based on process entries in /proc, owned by your UID, how would you work to find out which processes these actually represent?
What does he mean? If I run the command (considering that my username is sl33p):
Code:
$ps -u sl33p
...gives me the right answer?
The ps man page says:
-u userlist
Select by effective user ID (EUID) or name.
This selects the processes whose effective user name or ID is in userlist. The effective user ID describes the user whose file access permissions are used by the process (see geteuid(2)). Identical to U and --user.
user@host$ killall -9 -u user Will it definitely kill all processes owned by user (including forkbombs)?
No new processes is spawned to user from other users. No user's processes are in D-sleep and unkillable.No processes are trying to detect and ptrace or terminate this started killall (but they can ptrace or do other things with each other) There is ulimit that prevents too much processes (but killall is already started and allocated it's memory)
E.g. if killall will finish untampered and successfully is it 100% that no processes are left with this uid? If no, how to do it properly (with standard commands and no root access). Will SysRq+I definitely kill all things (even replicating)?
All the kill idle user processes scripts I've seen don't take into account that the user might have multiple sessions open. Such is the case with one of our clients. Currently, every hour or two I need to do the following:
This will get the TTY and idle time for all users.
For each idle time over a half hour, I do the following (TTY is the TTY from the previous command with a space.
I then kill those processes.
There must be a way to do this automatically in a bash or perl script. I've tried both, but can't seem to get things to work properly.
I would like to give a non-root user (nicollet) the ability to detect and send a signal to processes started by Apache2 (those processes are FastCGI scripts and the signal tells them to empty their cache). The processes are owned by the web user (www-data), and I'm running on Debian unstable.
I can't find any way to have the nicollet user see those processes.
The processes are running and can see by both root and www-data:
root@linux-01:~# ps -Af | grep baryton
www-data 17649 17648 0 10:27 ? 00:00:00 baryton
www-data 28145 1 0 Nov01 ? 00:00:12 baryton --bot
root 18701 18700 0 10:46 pts/0 00:00:00 grep baryton
root@linux-01:~#
[Code]....
The most surprising is that the grep process is indeed run by www-data (because it's started from a setuid executable) and is visible, but the baryton process isn't.
What's going on here? Why can ps run by www-data show those processes, but ps run by a setuid executable running as www-data cannot, when it's started by nicollet?
Few days ago, the server did not respond to a ssh request from a user at night. A user tried to check what went wrong with computer and tried to login from terminal next morning. As the computer was unresponsive, he somehow decided to boot it by turning the power off. To make the story short, the server rebooted; however, he can't login to his account. Actually, the server could not start some processes; but was able to ask user to enter his account username. Even though, he enters the correct username and password, server does not accept the request. I also could not login as root.
I just checked the server logs by booting it in single user mode. Here are some interesting lines:
Before the reboot:
irqbalance : can't balance irqs on a uniprocessor system: failed
After the reboot:
irqbalance : can't balance irqs on a uniprocessor system: failed
fsck:
fsck /: (this is repeated 900+ times)
[code]....
Normally all I/O goes through the kernel so that it can schedule the operations and prevent processes from stepping on each other. A few special user processes are allowed to slide around the kernel, usually by being given direct access to I/O ports. X servers are the most common example of this isn't it ? give examples for any other processes that are allowed to slide around the kernel ?
View 3 Replies View RelatedI'm trying to get the end result to have the same format as this as well:
1 bin
2 daemon
67 erozner
[code]....
Where the numbers are the number of processes being run by the user (the name right next to it).if I input the command egrep myFile into the terminal, it should look for every line with the letter x in myFile, right?
Are there any tools to view/edit user space memory of running processes on Linux?
It would be a great learning tool.
I have some domains on a VPS server. Typical account memory usage for all domains runs at 50% of available, but I have a problem. One domain is causing me trouble because intermittently traffic will spike on that domain, causing so many requests within 1 min that I exceed my memory allocation for my entire VPS package. Apache is then killed but the virtualization software and Apache must then be restarted.
A sample snippet from tops right before the sever went down would like like this:
All of that memory usage adds up. I would like to "throttle" the number of processes that user/domain can run. I think this would be a quick and easy way to keep the domain from taking down my entire VPS. My understanding is that I could do this with the /etc/security/limits.conf file.
Is that correct?
I have never done this before. Do I want to set a hard or soft limit? I think if I wanted to limit the number of processes for "coldclim" to 15 I would add a line to limits.conf like this:
Code:
Assuming that is correct, can anyone tell me how the website would respond once it reached its limit? Would visitor queries become sluggish, or would the website not come up for them at all?
I have a problem with the permission of the directories under /proc, they are readable and accessible only by Owner (they have permission 500 instead of the usual 555) As a consequence, the processes are visible only to the Owners or to Root. For exampleif I want to check if there is mysql
I see it only with the user mysql or with root because the directory has permission 500
This problem obstacles the functioning of some applications that should check the existence of some processes managed by other users. At the beginning all was working well. But after a while the problem appeared and I dont know which is the reason of it. how to restore the standard management of permissions of / proc?]
I have a Ubuntu server Maverick 10:10.
is there any possible way to hide currently running processes from an user? This means I do not want him to know about what programs/processes does any other user but him run. In short words if that user runs 'ps -aux' he should get only his processes.
View 3 Replies View RelatedFew days ago, the server did not respond to a ssh request from a user at night. A user tried to check what went wrong with computer and tried to login from terminal next morning. As the computer was unresponsive, he somehow decided to boot it by turning the power off. To make the story short, the server rebooted; however, he can't login to his account. Actually, the server could not start some processes; but was able to ask user to enter his account username. Even though, he enters the correct username and password, server does not accept the request. I also could not login as root.
I just checked the server logs by booting it in single user mode. Here are some interesting lines:
Before the reboot:
irqbalance : can't balance irqs on a uniprocessor system: failed
After the reboot:
irqbalance : can't balance irqs on a uniprocessor system: failed
fsck:
This might be something related with shadow file.
Here is part of /etc/shadow
this is scary, bunch of vmware-user-wra processes stall cpu 100%!! What's going on? Server has just been restarted! Bere I restarted, the root started all this vmware-user-wra!! I was configuring vncserver! After restart, it's started by user roo300 which I have used to login via SecureShell!
Code:
top - 20:20:29 up 4 min, 85 users, load average: 76.57, 35.14, 13.60
Tasks: 629 total, 90 running, 539 sleeping, 0 stopped, 0 zombie
Cpu(s): 1.5%us, 98.5%sy, 0.0%ni, 0.0%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 3873304k total, 369500k used, 3503804k free, 50492k buffers
[code]....
I have what I think is a somewhat different failure of standby than I've seen listed on other threads, and I'm stumped.The system hangs on this for a while, then comes back to the login screen without going into standby. This ONLY HAPPENS on a SECOND standby attempt--the first standby after booting ALWAYS succeeds.The standby log doesn't indicate any failures.I had made other changes previously that temporarily got standby working consistently:/etc/default/grub: GRUB_CMDLINE_LINUX_DEFAULT="quiet splash usbcore.autosuspend=-1"
View 1 Replies View Relatedi am using putty to connect to the linux server and i am using nano as my text editor to write a bash script.
this is my script:
echo "Please enter your Username"
read userName
userName= grep $USER /etc/passwd | cut -d: -f5
echo "Welcome " $userName | cat >> output.txt
the problem i have is that when i enter my username, the output (my real name) does not display in the output.txt. instead it displays in putty. so when i run my script in putty it shows the message to enter username and after i enter my username my real name appears below it. i want it to show in the output.txt
I want to add 50 new users, not on the server yet I want to add them all to group Accounting - with 1 option, not user by user I want to setup a default password for them all, and have it say something like 'You must now change password or no access will be permitted' Any other options I also want to do once, not for each user?
View 3 Replies View RelatedI am using mint 8 for a 2 weeks, I am noob to linux but I like Mint than any other linux distro which is great alternative to windows. I have a problem regarding password reseting.
1. My laptop automatically get logged in without asking user name and password.
2. I tried to change password for newly created user and root user using graphical way but it does not work.
2. I can perform administrator task using only OEM user which is default inbuilt user of mint.
How can make my laptop to ask password when mint get booted? How to change password for other users?
I've looked everywhere but I can't find where to change the default box for incoming mail, or am I on the wrong track. It's a nuisance having to change folders and I can't configure wastebin to empty on exit.And I can't get kmail to import from evolution. Do I have to go to the evolution storage and do it manually, and if so, how do I do that?
View 1 Replies View RelatedI am using the sudo command to log on locally as another user by the following command:
sudo -u theotheruser -s
or
sudo -u theotheruser sh
As I see it, this initiates a new shell with the mentioned other user.However, this doesn't load that users profile from his home directory.Is there a way to automatically read the users profile when login in with selected command? I am mostely interested in getting a working prompt when logged in.
I'm developing an application in which one user must run java software that I'm compiling as another user. I wanted to give user A permission to see the bin direcory of my workspace, which is in the home directory of user B. I was wondering how can this be done? I gave the bin direcotry full read/execute premissions, but since it's in my home directory user A can't navigate to it.
I know there are a few ways I could get around the problem but they arn't very elegant. I was wondering if there is a simple method for giving a user access to a specific directory without giving access to all the parent directories. I tried symbolic link but user A still can't access it, and a hard link to a directory isn't allowed in Linux. I don't feel like making a hard link to every single file in the bin directory, and I'm not sure that would work anyways, since every recompile overwrites them.
What is the difference between creating a "regular" user and creating a "system" user on Linux?
For example:
Code:
adduser john
Code:
adduser --system john
Similarly it seems there are normal groups and system groups. Doing an internet search and reading man pages does not give much information on the whole concept of system and regular user/group.
How do I disable and change the user password using SSH on a Linux
View 3 Replies View RelatedI'm looking for a Linux command that can change ownership of all files belonging to a given user,preferably in a targeted directory, to another specified user. My dream command would look something like this. chuser -R --olduser tom --newuser jerry
This is my scenario... I have a backup file (.tgz) with user and group information preserved in it. It was taken from a web server running Apache and MySQL. The files in the backup are from across the system and contain files from several different users and several system type accounts and it is key that when restored on the new server the settings are not lost. The problem is that the users on the machine the files are being restored to don't match the ones in the backup file. For instance both machines had a MySQL user but they have different user ids and there are several user ids that existed on both machines that belong to different users. This means there is no way to sync the users on the new machine to the ones on the old machine. I can find all the users files with the find command like this...
find /decompressed-backup-dir -uid 1050
or
find /decompressed-backup-dir -user tom
If, as I suspect, there is no way to do what I want with a single command then perhaps there is a way to pipe the results of the find command to another command to handle the ownership change?
I could do this with a PHP script but there are 4GB and tens of thousands of files in the backup so I don't want to use PHP or Perl but I would be happy with a shell script that could handle it.
i'm new to linux and just installed Ubuntu and decided to play around with it. i just executed
Code: useradd test which supposedly creates a folder in the home directory '/home/test' but when i look in there i can't see it i also did a
Code: grep test /etc/passwd which returns: 'test:x:1001:1001::/home/test:/bin/sh' which i believe means it is meant to exist.
Addendum: I have also now noticed that when i log in and log back in i have the option to login as 'test' but it prompts me for a password which i did not set :s
How would you make NIS user information override local user information on client systems? This is what I think is right? Add nis on the passwd registration file on the second line Is this correct?
View 1 Replies View RelatedI am writing a simple application that will run as user foo (i.e. Ubuntu user foo).However, the application will connect to my database as (database user foobar). IIRC, database users have nothing to do with Linux system users - but I just need to clarify that.So can an app launched to run as user 'foo', connect to a database as user 'foobar'?
View 1 Replies View RelatedI have a few multi-user servers in an academic laboratory. I am having a problem with some users maxing out the available RAM, causing such sever slowdowns the machine essentially crashes. My servers are Dell Power Edge's running Ubuntu 8.10 Server Edition (Not my choice). I would like to set a maximum limit on the amount of ram a user can utilize. This morning I experimented with setting limits via /etc/security/limits.conf and using ulimit. Neither of them prevented my test program, a simple infinite loop of mallocs, from crashing the server.
View 7 Replies View RelatedPrelude: OpenSUSE 11.2 (2.6.31.8-0.1-desktop), installed Novell client 2.0 SP2 (novell-client-2.0-sp2-sle11-i586.iso).
I found that if any usual user is logged into a NDS-tree, then _local_ root has full access to user's network shares, including the user's home directory located on remote Netware-server. Is it by design or
have I missed something? Nevertheless in windows local admin has no access to network resources mounted of any other user. If you runas shell (as admin) then admin in principle can't "see" network shares which were mounted (connected) by other users - they are accessible ("visible") per session.
Take a physical user FRED. FRED is a linux user ( known by linux on his laptop ) FRED is a Samba user ( Known by samba on the samba pdc server ) When he logs locally (with username/password) on its standalone laptop (with no network), he is known as FRED:user. He access his data in /home/FRED/. When he logs through samba (with username/password) on the domain MY_DOM, he is known as MY_DOMFRED:MY_DOMdomain user. He access his data in /home/MY_DOM/FRED/. ) Is it possible that the human FRED has only one repository and have full access to its repository regardless of how it was connected. If yes, how to do it
2) If not, Is it possible that the human FRED has full access to /home/FRED/.............. and /home/MY_DOM/FRED/.