Good Examples Of Bash Scripts

Hi All,
We have some shell scripts which will send emails about backup, alerts etc using mail command. Example.
Code:

echo "Test Mail" | mail -s "Test" me@mydomain.com

I guess the above command just connect port number 25 of our mail server even if we do not define any port number. Now I would like add smtp port number as 587 in all of the bash scripts. I googled for this but could not get whatever I am expecting. So expecting your kind reply to define smtp port number as 587 in all of the bash scripts.

Thanks in advance.

Does anyone know a way to copy two files to multiple computers? I'm thinking of scp as the flavor of linux we're using does not include rdist.

I've read that scp can't copy multiple files, however maybe some scripting genius has figured out a way. Running two scripts (one for each file), is perfectly ok!

If anyone care to post very clear examples (i'm definitely not a programmer...) of scripts, etc, that would be great.

Thanks in advance to all those who can help!

I am currently doing my project in NS2. i need to analyze my tracefile with xgraph. so i am in need of AWK scripts that are used to generate xgraph(eg:Time vs Throughput). Can any one pls help me??

Hi all,

How do i make

Code:

[alan@racnode1 scripts]$ echo alan{1..3}
alan1 alan2 alan3

to

Quote:
alan1
alan2
alan3
instead ?


Tried -e + /n to no avail.
Code:

[alan@racnode1 scripts]$ echo alan{1..3}\n
alan1n alan2n alan3n
[alan@racnode1 scripts]$ echo -e alan{1..3}\n
alan1n alan2n alan3n
[alan@racnode1 scripts]$ echo -e "alan{1..3}\n"
alan{1..3}

[alan@racnode1 scripts]$

Thanks.

Regards,
Noob

Hello,

I cannot understand why the symlink I have put in /etc/cront.daily won't work. It is very possible I am wrong, but my understanding is that cront.{daily,weekly,monthly} works fine with symlinks.

Basically it is double symlink-ed. ls -la on /etc/cron.daily looks like this:

Code:

... 
lrwxrwxrwx  1 root root    49 Nov 27 18:26 rsync_mysql_backups.sh -> /home/myuser/scripts/bash/rsync_mysql_backups.sh
...

Now, ls -la on /home/myuser/scripts looks like this:

Code:

...
lrwxrwxrwx 1 myuser myuser    26 Sep 20  2013 scripts -> /media/md1_storage/scripts
...

I couldn't see anything suspicious in syslog, so I installed postfix in the hope that I will get some sort of information there. Nothing... I also redirected the output of the script to a file in /home/myuser/log.txt but nothing there. The file was not even created.

I am not doing anything mad in the script, I am just synchronising a local directory with a remote one like this:

Code:

/usr/bin/rsync -avzx -e 'ssh -i "/home/myuser/.ssh/myremotehost/id_rsa"' /media/md1_storage/backups/stuff/ myuser@myremotehost:/srv/backups/stuff/ >> /home/myuser/log.txt 2>&1;

As other people suggested in similar threads, I have verified that
Code:

test -x /usr/sbin/anacron

is false, which will result in the execution of the second part of the entry in /etc/crontab:

Code:

25 6    * * *   root    test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.daily )

Any input will be much appreciated. I know I am doing something wrong, but I just cannot see it right now... How can I gather more debugging which will help me understand what's going wrong?

Thanks!

I am looking to display the w (who) command to show only the

User TTY IDLE


http://screencast.com/t/vXb74kguJ

13:15:38 up 8 days, 16:48, 47 users, load average: 1.47, 0.95, 0.51
USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT
rf3 pts/0 192.168.11.72 05:58 48.00s 6.60s 0.00s -bash
user21 pts/1 192.168.21.177 04:32 8:41m 0.05s 0.00s -bash
user7 pts/2 192.168.11.114 17Mar15 6days 1.07s 0.00s -bash
user7 pts/3 192.168.11.114 20Mar15 4:54m 9.75s 0.00s -bash
user6 pts/4 192.168.11.85 11:02 7.00s 55.58s 0.01s -bash
user14 pts/5 192.168.11.183 05:06 29:08 2.80s 0.01s -bash
user14 pts/6 192.168.11.155 05:30 13:28 2.75s 0.00s -bash
user23 pts/7 192.168.11.62 05:48 25:09 0.95s 0.00s -bash
rf5 pts/8 192.168.11.118 05:58 6:51 5.30s 0.01s -bash
user2 pts/9 192.168.11.140 08:34 1:19 44.74s 0.00s -bash
user14 pts/10 192.168.11.141 06:02 12:14 9.46s 0.00s -bash
rf12 pts/12 192.168.11.69 06:02 2:07 9.44s 0.00s -bash
root pts/13 localhost.locald 12:29 9:10 0.05s 0.05s -bash
rf6 pts/14 192.168.11.79 06:04 14.00s 9.05s 0.00s -bash
user14 pts/15 192.168.21.113 06:23 11:29 1.71s 0.00s -bash
user5 pts/16 192.168.11.126 06:24 6:56 4.59s 0.00s -bash
user5 pts/17 192.168.11.126 06:25 6:19 31.59s 0.01s -bash
user11 pts/18 192.168.11.125 06:26 28:10 2.90s 0.01s -bash
user12 pts/19 192.168.21.123 06:35 13:16 0.88s 0.00s -bash
rf7 pts/20 192.168.11.80 06:35 2:06 7.64s 0.00s -bash
user12 pts/21 192.168.21.123 06:36 41:55 0.12s 0.00s -bash



So far I have this

w | awk {'printf ("6s\ts\n", $1, $2, $3, $5)'} |more
13:20:16 up
USER TTY
rf3 pts/0
user21 pts/1
user7 pts/2
user7 pts/3
user6 pts/4
user14 pts/5
user14 pts/6
user23 pts/7
rf5 pts/8
user2 pts/9
user14 pts/10
rf12 pts/12
root pts/13
This only shows the 2 columns



w |awk '{print $1, $2, $3, $5}'

13:21:01 up 8 16:53,
USER TTY FROM IDLE
rf3 pts/0 192.168.11.72 20.00s
user21 pts/1 192.168.21.177 8:46m
user7 pts/2 192.168.11.114 6days
user7 pts/3 192.168.11.114 4:59m
user6 pts/4 192.168.11.85 3:42
user14 pts/5 192.168.11.183 34:31
user14 pts/6 192.168.11.155 18:51
user23 pts/7 192.168.11.62 30:32
rf5 pts/8 192.168.11.118 12:14
user2 pts/9 192.168.11.140 1.00s
user14 pts/10 192.168.11.141 17:37
rf12 pts/12 192.168.11.69 30.00s
This shows some what hard to read and the columns don't line up correctly


is there a way to tab them in to columns that line up properly, or even something similar to the TOP command where the list will keep refreshing?

Apologies. I've been out of Unix for 14 years, and the gears have rusted. Also, Unix has changed - enough similarities to memory that I'm pretty comfy though.

Glad to see lots of info available via google. However changes are going to take getting used to. Have set up a testbed of 3 nearly identical machines, hoping to make an (at home) private network where I can automate installs and set-ups using NIS and NFS (Similar to work I once did).

Have found useful scripts interspersed with comments, would like to copy and paste them to a bash script that:

Reads the line.
Echos the line.
Reads the reply.
Executes what is typed.

Essentially, by making myself type (or copy & paste) the commands I think I'll become familiar.

Figured I'd use a spreadsheet, select the file, and paste into column B of the spreadsheet. In column A I'd paste:

echo "

and in column C I'd paste:

"

Then I'd cut and paste into a text document, insert the lines:

read A
$A

behind every command necessary to the actual task.

Figured I'd have to escape the ' and ".

Ran a test (test.bash):

#!/bin/bash
for i in `seq 1 10`;
do
echo "Enter a command:"
read A
echo "Trying $A"
$A
done

works fine when I type

ls -alg

but not so when I type

ls -alg | grep dwrx

so I'm wondering if someone has a suggestion?

Thanks for any ideas.

I can't believe I wrote a looong message and it logged me out when I tried to submit it.

So anyway, in short lines:

- I have a network of sites where all sites share same "images" folder
- I have created /home/_images/entities and symlinked it from all websites
- It works great with Apache, when I open /images/ on any of the sites I get list of images and can view them

The problem is suPHP which changes process ID of the PHP script to the file owner ID, so when I load site1.com, all scripts are executed as user1 (and files/folders created with those scripts belong to user1:user1). When I load site2.com, all scripts are executed as user2 (and files/folders created with those scripts belong to user2:user2). All these users do NOT belong to the same group, and I wouldn't like to change that as it is cPanel/WHM server so I'm afraid I'll screw something up if I change (primary?) group of all users.

Therefore I need to set it up in such way that all newly created folders and files under /home/_images/entities (owned by root) have read/write permissions for everyone.

Here's the command I used:

Code:

setfacl -Rdm o::rwx /home/_images/entities

To check it:
Code:

root@server1 [~]# getfacl /home/_images/entities/
getfacl: Removing leading '/' from absolute path names
# file: home/_images/entities/
# owner: root
# group: root
user::rwx
group::rwx
other::rwx
default:user::rwx
default:group::rwx
default:other::rwx

This looks fine, however when I try upload an image via site1.com it looks like this:

Code:

root@server1 [/home/_images/entities]# ls -l
total 24
drwxrwxrwx+ 5 root    root    4096 Jan 14 06:25 ./
drwxrwxrwx  5 root    root    4096 Jan 12 13:08 ../
drwxrwxr-x+ 3 user1   user1   4096 Jan 14 06:25 1/

And in folder "1" is the image (and thumbs folder):

Code:

root@server1 [/home/_images/entities/1]# ls -l
total 236
drwxrwxr-x+ 3 user1   user1     4096 Jan 14 06:25 ./
drwxrwxrwx+ 5 root    root      4096 Jan 14 06:25 ../
-rw-rw-rw-  1 user1   user1   225569 Jan 14 06:25 689048f221ab7c556f4d482a9d92b2d6.jpg
drwxrwxr-x+ 2 user1   user1   4096 Jan 14 06:25 thumbs/

My questions:

1) Why newly created folders do not have "write" permissions for everyone else [not user and/or group]? If I upload first image from site1.com, then I can't upload other images from any other site, while all sites can display them.

2) What is the + at the end of permissions list? (drwxrwxr-x+)

3) Why newly created files have only "rw" permissions for user, group AND everyone else, and not execute permissions? I don't actually need execute flag set here, but from my command you can see I've set "o::rwx" so it should be there (or not?)

Actually the real problem is #1 - other users can't write to this folder so users can't upload images from other sites nor other sites can create (missing) thumbnails.

Hi all,

I am trying to write a script that syncs files from source to destination. I have one centralized server that can ssh to any servers without pw. Now when I run the script, it can ssh to source server perfectly fine, but you need to enter password for destination server. Was wondering how I can clean this up before I start using case statements

Below is a sample I wrote

#!/bin/bash

#This scripts syncs shit

echo "Type in ID: "
read ID

echo "Type in Server : " #source server
read S

echo "Type in Destination Server: "
read DS

if [ $S == 9 ]; then
ssh -t "root@"$S"webserver1" "rsync -av /home/rlui/"$ID "root@"$DS"webserver2:/home/rlui/";
ssh -t "root@"$S"webserver1" "rsync -av /home/rlui/tmp/"$ID "root@sl"$DS"webserver2:/home/rlui/tmp/"
exit 1

where S and DS are cluster numbers

I apologize in advance if I am not clear on anything

Hi

I'm focusing on getting my head around interactive v non-interactive shells, both non-login and login. Basically what scripts are run and how local and global variables behave.

I'm pretty much there except for 'non-interactive login shells'. I understand that 'non-interactive' shells are started when a script is run. However, if I start my script with #!/bin/bash --login, then a 'non-interactive login' shell will be started.

In my mind I would have expected this to be the same as logging in from scratch, albeit without a user\password prompt. In this case I would have thought that any exported variables from the parent shell would be blown away. This doesn't appear to be the case. The 'non-interactive login' shell appears to inherit the environment of its parent 'interactive' shell.

Can anyone explain the purpose of a 'non-interactive login' shell and how they behave in this regard.

Hope this makes sense.

Cheers

Mike