After bash script completion, change variable and restart script

Question

I have some working script, in start of which I enter start parameters (server IP, user login and root login), and every time, when I need to restart this script on another server, I need to edit script, to change server IP variable. How can I change this, to enter a bunch of IP addresses in variable(s), maybe in some array and when script finishes with first IP, it goes to second, and so on to the end of IP list?

Script example:

##!/bin/bash

serv_address="xxx.xx.xx.xxx"

"here goes some script body"

chepner · Accepted Answer · 2016-08-25 13:34:17Z

1

You do indeed want an array, which you can then iterate over with a loop.

serv_address=(xxx.xx.xx.xxx yyy.yy.yyy.yy)

for address in "${serv_address[@]}"; do
    if ! ping -c 1 "$serv_address"; then
        echo "$serv_address is not available" >&2
        continue
    fi
    # Do some stuff here if the address did respond.
done

edited Aug 25, 2016 at 13:34

answered Aug 25, 2016 at 12:22

chepner

538k77 gold badges594 silver badges746 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Vasyl Stepulo Over a year ago

Thanks, it works! But my script contains a few checks. Something like: if ! ping -c 1 $serv_address &>/dev/null; then echo "$serv_address is not available" exit 1 fi In case of array - how to rewrite this check that script isn't exit, but goes to next IP address in array?

chepner Over a year ago

bash has continue and break commands that work as you might expect from other languages: continue moves directly to the next iteration of the loop, and break exits the loop early.

sjsam · Accepted Answer · 2016-08-25 12:22:08Z

1

use a text file for storing ips like

$ cat ip.txt
xxx.xx.xx.xxx
xxx.xx.xx.xxx
xxx.xx.xx.xxx
xxx.xx.xx.xxx

then modify your script

#!/bin/bash
while read ip
do
#some command on "$ip"
done<ip.txt # Your text file fed to while loop here

Or use bash array

declare ip_array=( xxx.xx.xx.xxx xxx.xx.xx.xxx xxx.xx.xx.xxx )
for ip in "${ip_array[@]}"
do
#something with "$ip"
done

Both gives you the flexibility to add/delete IP addresses later.

answered Aug 25, 2016 at 12:22

sjsam

22k6 gold badges63 silver badges114 bronze badges

1 Comment

Vasyl Stepulo Over a year ago

Thanks, it works! But my script contains a few checks. Something like: if ! ping -c 1 $serv_address &>/dev/null; then echo "$serv_address is not available" exit 1 fi In case of array - how to rewrite this check that script isn't exit, but goes to next IP address in array?

Collectives™ on Stack Overflow

After bash script completion, change variable and restart script

2 Answers 2

2 Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related