[SFS] Load-balancers, like light-sabers, are (mostly) bullshit

Wed, 10 Jun 2015 14:26:41 -0600 (MDT)

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Go to YouTube and search for "Light-sabers are bullshit" 

You're welcome. Now, to add to your happy. 

If you don't do clusters and have a basic understanding of DNS, you probably want to stop reading here. 

It turns out that having multiple A records for a name does most of what a load-balancer does. 

Almost every client program (*definitely* web-browsers) are smart enough to try the next address when they're refused connection on a service-port . So, you add two A records with the key "www.sofree.us" and when one web-server stops answering, the *client* will automatically try another address. Yes, really. So, if you have two A records, and http server is down, the clients will automatically move to the other. I always thought that half the clients would just hang or get errror messages. Nope. It just works. No need for haproxy or keepalived or an expensive hardware device, most of the time. 

Remember that I said that I mostly wanted to work here so I could learn stuph from the brilliant Chris Fedde? I'm paid. 

-- 
David L. Willson 
Teacher, Engineer, Evangelist 
RHCE+Satellite CCAH Network+ A+ Linux+ LPIC-1 UbuntuCP NovellCLA 
Mobile 720-333-LANS(5267) 
http://sofree.us 

This is a good time for a r3VOLution. 

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div style=3D'font-family: times new roman,new york,times,serif; font-size: =
12pt; color: #000000'>Go to YouTube and search for "Light-sabers are bullsh=
it"<br><br>You're welcome. Now, to add to your happy.<br><br>If you don't d=
o clusters and have a basic understanding of DNS, you probably want to stop=
 reading here.<br><br>It turns out that having multiple A records for a nam=
e does most of what a load-balancer does.<br><br>Almost every client progra=
m (*definitely* web-browsers) are smart enough to try the next address when=
 they're refused connection <b>on a service-port</b>. So, you add two A rec=
ords with the key "www.sofree.us" and when one web-server stops answering, =
the *client* will automatically try another address. Yes, really. So, if yo=
u have two A records, and http server is down, the clients will automatical=
ly move to the other. I always thought that half the clients would just han=
g or get errror messages. Nope. It just works. No need for haproxy or keepa=
lived or an expensive hardware device, most of the time.<br><br>Remember th=
at I said that I mostly wanted to work here so I could learn stuph from the=
 brilliant Chris Fedde? I'm paid.<br><br><div><span name=3D"x"></span>--<br=
>David L. Willson<br>Teacher, Engineer, Evangelist<br>RHCE+Satellite CCAH N=
etwork+ A+ Linux+ LPIC-1 UbuntuCP NovellCLA<br>Mobile 720-333-LANS(5267)<br=
>http://sofree.us<br><br>This is a good time for a r3VOLution.<span name=3D=
"x"></span><br></div><br></div></body></html>
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