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Check a server is up. If it isn't mail me.

Terminal - Check a server is up. If it isn't mail me.
ping -q -c1 -w3 brandx.jp.sme 2&>1 /dev/null || echo brandx.jp.sme ping failed | mail -ne -s'Server unavailable' [email protected]
2009-10-13 14:13:04
User: mccalni
Functions: echo mail ping
7
Check a server is up. If it isn't mail me.

Joker wants an email if the Brand X server is down. Set a cron job for every 5 mins with this line and he gets an email when/if a ping takes longer than 3 seconds.

Alternatives

There are 4 alternatives - vote for the best!

Terminal - Alternatives
curl -fs brandx.jp.sme 2&>1 > /dev/null || echo brandx.jp.sme ping failed | mail -ne -s'Server unavailable' [email protected]
2009-10-23 14:29:06
User: mccalni
Functions: echo mail ping
Tags: bash ping curl mail
2

Alternative to the ping check if your firewall blocks ping. Uses curl to get the landing page silently, or fail with an error code. You can probably do this with wget as well.

ping -q -c1 -w3 server.example.com >& /dev/null || echo server.example.com ping failed | mail -ne -s'Server unavailable' [email protected]
2010-09-08 12:19:29
User: brainstorm
Functions: echo mail ping
Tags: bash ping mail
2

For some reason the 2&>1 does not work for me, but the shorter stdout/stderr redirection >& works perfectly (Ubuntu 10.04).

nc -zw2 www.example.com 80 || echo http service is down | mail -s 'http is down' [email protected]
2010-09-08 13:18:16
User: putnamhill
Functions: echo mail
1

This version uses netcat to check a particular service.

Know a better way?

If you can do better, submit your command here.

What others think

seem not correct.

When i execute "ping -q -c1 -w3

i got exit status 0 and when executing "ping -q -c1 -w3 www.google.com 2&>1 /dev/null" i got 1 ....

Comment by zhuzhixin 373 weeks and 1 day ago

zhuzhixin, what distro you using? This using bash on Jaunty.

From the ping man page

...

ping is part of iputils package and the latest versions are available in source form at http://www.skbuff.net/iputils/iputils-current.tar.bz2.

...

-q Quiet output....

-c count

Stop after sending count ECHO_REQUEST packets. With deadline option, ping waits for count ECHO_REPLY packets, until the timeout expires.

-w deadline

Specify a timeout, in seconds, before ping exits regardless of how many packets have been sent or received....

Comment by mccalni 372 weeks and 2 days ago

I think maybe your firewall eats ping replies? Try an internal machine address and/or something you know you get ping replies from. My corporate firewall eats pings from google, yahoo, et al, but at home I can ping them fine.

Comment by mccalni 372 weeks ago

I don't think the part "2&>1 > /dev/null" does what you think it does.

It's 2>&1, not 2&>1, and the 2>&1 should follow the >somefile part. It says send stderr to where I just sent stdout. Or you could have used >&. See these examples:

>a ll a b 1

ls: cannot access b: No such file or directory

ls: cannot access 1: No such file or directory

-rw-r--r-- 1 splante 20000 0 Apr 7 18:08 a

# your way just creates a file named 1 with stderr ll a b 2&>1 >/dev/null cat 1

ls: cannot access b: No such file or directory

ls: cannot access 2: No such file or directory

rm 1

# this doesn't send stderr to /dev/null

ll a b 2>&1 >/dev/null

ls: cannot access b: No such file or directory

ll a b 1

ls: cannot access b: No such file or directory

ls: cannot access 1: No such file or directory

-rw-r--r-- 1 splante 20000 0 Apr 7 18:08 a

# both of these work as expected

ll a b >/dev/null 2>&1 ll a b >& /dev/null
Comment by splante 296 weeks ago

Man, thanks a lot, but my ping don't understand standarts stderr. I was pinging 8.8.8.8 and 8.8.4.15 (it's unroutable) and all outputs are same. What's hapen's guys? I using AltLinux 4.01.

Comment by Arkey 291 weeks and 1 day ago

I use modifide script:

while true; do /bin/ping -q -c1 -w3 8.8.8.8 2&>1 /dev/null || echo "8.8.8.8 ping failed at $(date +%D) $(date +%H:%M:%S)" >> /var/log/ping.log; sleep 10; done &

both 2&>1 and 2>&1 are same for me

Comment by Arkey 291 weeks and 1 day ago

2016-6-7 leilei

"Tweed is an excellent fabric especially when you are living in place like London. London is known for its cold weather and in such climate, tweed works absolutely fine. One of the biggest advantages of buying a tweed suit is that you it can be worn all together or can be incorporated separately into pieces in your wardrobe. Tweed suits in London is quite famous amongst men. So let us understand, what exactly tweed fabric is.

What is Tweed?

Tweed is a warm rough to touch fabric and was originated in Scotland. The reason why tweed suits in London are famous is because of its loose weave which makes it flexible and comfortable during winters. The tweed fabric is referred to the weave of fabric; therefore when you see different kinds of tweed, it would tell you the pattern it has been woven. One of the most popular kinds of tweed is the herringbone tweed which a diagonally v-shaped black and white weave. The herringbone tweed gives a rich visual texture and known for its versatility.

Ways to wear Tweed in winters

Everybody needs to wear warm clothes during the winter month to protect from the chilly weather outside. However, many people think that they might have to compromise fashion during those chilly months. Not now! There are many fabrics that you can use to protect yourself from the weather as well as still enjoy great looks. Tweed is one of the fabrics that can make you awesome even in winters as well. Below are some ways of how you can incorporate tweed with other pieces in your wardrobe

"

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"Casually ? if you are a starter with tweed then it is recommended to start with plain variety of tweed. You can wear a tweed jacket with dark blue jeans and high boots. Incorporate a neutral t-shirt or a winter shirt under the jacket.

At work ? Tweed suit in London are quite popular as one of the formal attires. Heavy woven tweeds can make you look older, so try buying tweed suits in London that are finely weaved and pair it with your regular shirts like white or blue with smart formal shoes. Believe it or not, it can win you praise at work.

Accessorise ? Apart from wearing tweed suits in London as attire you can even use accessories made out of tweed. Tweed caps, laptop bags, scarves, gloves are a smart way to incorporate tweed in your winter collection. It is also a safe way of using tweed fabric if you are not too comfortable wearing it. There is even footwear that has tweed as their centre fabric and looks awesome.

Taking care of Tweed

Though the fabric boasts itself about being tough and rugged, it still requires a good care to use it for coming years as well. Due to its weave structure it often pick up dirt and stains that can get hard to remove. Make sure you take your tweed clothes for dry cleaning as washing them in washing machines can make them shrink. Also, keep them in cool dry place so that they do not get attracted by moths.

"

Comment by leilei3915 26 weeks and 3 days ago

Your point of view

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