If you're very busy and don't want to wait for a ping response, use it. This command will be waiting for a successful ping response, to play a sound file to warn you that the target host is available.
pcspkr have to be enabled! modprobe pcspkr xset b on
Change the IP address from 127.0.0.1 to the target machines ip address. Even if the target has ICMP (ping) blocked, it will show you what ports are open on the target. Very handy for situations where you know the target is up and online but wont respond to pings. Show Sample Output
export THISOS="`uname -s`" if [ "$THISOS" = "SunOS" ] then export THISRELEASE="`uname -r`" ping1() { ping -s $1 56 1 | egrep "^64"; } elif [ "$THISOS" = "AIX" ] then export THISRELEASE="`uname -v`.`uname -r`" ping1() { ping -w ${2:-1} $1 56 1 | egrep "^64"; } elif [ "$THISOS" = "Linux" ] then export THISRELEASE="`uname -r`" ping1() { ping -c 1 -w ${2:-1} $1 | egrep "^64"; } fi
This version combines the best of the other suggestions and adds these features: 1. It scans a /16 subnet 2. It is very fast by running the ping commands in the background, running them in parallel. 3. Does not use the "-W" option as that's not available in older ping versions (I needed this for OS X 10.5)
Execute commands serially on a list of hosts. Each ssh connection is made in the background so that if, after five seconds, it hasn't closed, it will be killed and the script will go on to the next system. Maybe there's an easier way to set a timeout in the ssh options...
Cleaned up and silent with &>/dev/null at the end. Show Sample Output
Super fast way to ftp/telnet/netcat/ssh/ping your loopback address for testing. The default route 0.0.0.0 is simply reduced to 0. Show Sample Output
This helps me determine which repo I want to use for downloading ISO files Show Sample Output
Changelog: Changing ping to "ping -A -c1 -w10" - targeting a quick and reliable ping, even on slow networks.
IMPORTANT: You need Windows PowerShell to run this command - in your Windows Command Prompt, type
powershell
Uses sajb to start a PowerShell background job that pings an IP host every 10 seconds.
Any changes in the host's Up/Down state is time-stamped and logged to a file.
Date/time stamps are logged in two formats: Unix and human-readable.
A while(1) loop repeats the test every 10 seconds by using the sleep command.
See the Sample Output for more detail.
I use this command to log Up/Down events of my Motorola SB6141 cable modem (192.168.100.1).
To end the logging, close the PowerShell window or use the "exit" command.
Show Sample Output
activate the first alert and the next ones are activated automatically. Show Sample Output
Bash scrip to test if a server is up, you can use this before wget'ing a file to make sure a blank one isn't downloaded.
This command are using by me for checking connection with Internet. Show Sample Output
You need to have mtr installed on your host.
A simple way to find all machines on a network subnet is pinging a broadcast address (-b flag). First run ifconfig ifconfig. Then use "Bcast" address and '-b' flag in ping Show Sample Output
Not really an easier solution. But an example using && for (if last command returned 0). You can use || for (if last command returned other than 0).. Show Sample Output
Every 20 minutes ping host with IP address 192.168.0.14. If it's not 'alive' or not reachable, then display something eye-catching (here xeyes) on the desktop.
Hint for newbies: edit crontab with
crontab -e
sending packet by ping if sending more high packet root needed... Show Sample Output
Quick and dirty one-liner to get the average ping(1) time from a server. Show Sample Output
Every 20 minutes test if host with IP 192.168.0.14 is 'dead' or not reachable. The line should be put in your crontab file.
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