sysadmin

I've searched around a bit for similar questions, but other than running one command or perhaps a few command with items such as: ssh user@host -t sudo su - However, what if I essentially need to run a script on (let's say) 15 servers at once. Is this doable in bash? In a perfect world I need to avoid installing applications if at all possible to pull this off. For argument's sake, let's just say that I need to do the following across 10 hosts: Deploy a new Tomcat container Deploy an application in the container, and configure it Configure an Apache vhost Reload Apache I have a script that

lsof is an increadibly powerful command-line utility for unix systems. It lists open files, displaying information about them. And since most everything is a file on unix systems, lsof can give sysadmins a ton of useful diagnostic data. What are some of the most common and useful ways of using lsof, and which command-line switches are used for that? To show all networking related to a given port : lsof -iTCP -i :port lsof -i :22 To show connections to a specific host, use @host lsof -i@192.168.1.5 Show connections based on the host and the port using @host:port lsof -i@192.168.1.5:22 grep ping

I need to set a system environment variable from a bash script that would be available outside of the current scope. So you would normally export environment variables like this: export MY_VAR=/opt/my_var But I need the environment variable to be available at a system level though. Is this possible? Jeremy Cantrell This is the only way I know to do what you want: In foo.sh, you have: #!/bin/bash echo MYVAR=abc123 And when you want to get the value of the variable, you have to do the following: $ eval "$(foo.sh)" # assuming foo.sh is in your $PATH $ echo $MYVAR #==> abc123 Depending on what you

I'm trying to do three things with the mv command, but not sure it's possible? Probably need a script. not sure how to write it. All files are in same folder. 1) Files ending with v9.zip should just be .zip (the v9 removed) 2) Files containing _ should be - 3) Files with Uppercase letter next to a lowercase letter (or lowercase next to an Uppercase) should have a space between them. So MoveOverNow would be Move Over Now and ruNaway would be ruN away [A-Z][a-z] or [a-z][A-Z] becomes [A-Z] [a-z] and [a-z] [A-Z] My favorite solution is my own rename script . The simplest example that maps to your

In Unix/Linux, how do you find out what group a given user is in via command line? groups or groups user This one shows the user's uid as well as all the groups (with their gids) they belong to id userid On Linux/OS X/Unix to display the groups to which you (or the optionally specified user) belong, use: id -Gn [user] which is equivalent to groups [user] utility which has been obsoleted on Unix. On OS X/Unix, the command id -p [user] is suggested for normal interactive. Explanation on the parameters: -G , --groups - print all group IDs -n , --name - print a name instead of a number, for -ugG

I'm attempting to code a script that outputs each user and their group on their own line like so: user1 group1 user2 group1 user3 group2 ... user10 group6 etc. I'm writing up a script in python for this but was wondering how SO might do this. p.s. Take a whack at it in any language but I'd prefer python. EDIT: I'm working on Linux. Ubuntu 8.10 or CentOS =) S.Lott For *nix, you have the pwd and grp modules. You iterate through pwd.getpwall() to get all users. You look up their group names with grp.getgrgid(gid) . import pwd, grp for p in pwd.getpwall(): print p[0], grp.getgrgid(p[3])[0] the grp

I'm a newbie in web server administration. I've read multiple times that flask built-in web server is not designed for "production", and must be used only for tests and debug... But what if my app touchs only a thousand users who occasionnaly send data to the server ? If it works, when will I have to bother with the configuration of a more sophisticated web server ? (I am looking for approximative metrics). In a nutshell, I would love to find what the builtin web server can do (with approx thresholds) and what it cannot. Thanks a lot ! There isn't one right answer to this question, but here