Go Back   HowtoForge Forums | HowtoForge - Linux Howtos and Tutorials > Linux Forums > Server Operation

Do you like HowtoForge? Please consider supporting us by becoming a subscriber.
 
 
Thread Tools Display Modes
Prev Previous Post   Next Post Next
  #1  
Old 26th June 2006, 16:32
geek.de.nz geek.de.nz is offline
Member
 
Join Date: Feb 2006
Posts: 65
Thanks: 0
Thanked 2 Times in 2 Posts
Send a message via ICQ to geek.de.nz Send a message via MSN to geek.de.nz
Default High Availability (Load Balancing) behind a firewall

My boss wants me to setup a load balanced system with a firewall filtering the traffic out and making this whole thing scalable for adding new machines into the cluster.

How would I go about this?

There would be a pyramid-like structure in his proposed system, where the firewall host would route traffic arriving to its internal servers (load balancers), which would in turn distribute it among the web and file servers in the inner network.

Is this a good solution? I would think that having (at least) 2 load balancers directly connected to the Internet would be desirable. Otherwise one has the single point of failure firewall. I would even go further and include the load balancers in the 2 firewalls, which are directly connected to the Internet and share a common virtual wan ip address.

So, I would have the following (simplest) setup:

2 Firewall hosts with the load balancers sharing 1 virtual ip
2 Web servers behind these firewalls which are to be load balanced by the firewalls

Does this sound like a better solution or do you think I should go with the pyramid approach? Does load balancing even justify then? Isn't the connection speed (10-100Mbit) a bottleneck rather than the server power (having very new hardware). Wouldn't the firewall, which needs to handle ALL connections be the bottleneck when it comes to using resources?

Might we even install webservers on the firewalls/load balancers as well to make use of their resources more efficiently or does that defeat the purpouse of a firewall?

With todays technology virtualisation (aka Xen, VirtualLinux) could be used as well to make use of all the resources of the firewall hosts while still completely separating the firewall from the load balancer and the maybe even installed web server on that system.

What would be the best solution? Is there a best solution? What does it depend on: Connection speed to the network/Internet of the various hosts, their processing power? How can one approximate the number of connections a host (firewall) can handle?

Is there a formula to calculate the number of firewall, load balancing and web server hosts which is optimal?

Can we measure the speeds of various tasks fulfilled by the hosts to approximate an optimal solution?

Any ideas would be greatly appreciated.

As I go on the load balancing howto I'm writing a script to automate this for loadb1 and loadb2, so that one can interactively enter the various bits of information necessary btw. If I get some good feedback on this and the system goes into production with the script working, I think I will post it somewhere in this forum.
__________________
Always mention at least your distribution/version! You can add it in your signature if you don't want to always type it. ;-)

Distributions:
Ubuntu 5.10 with custom kernel (2.6.16-suspend2),
Debian Sarge 3.1 and Etch

Please submit your ISP or Webhost to (free)
http://www.ihostnz.com
Reply With Quote
Sponsored Links
 

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
High Availability NFS Server Help - DRBD technick HOWTO-Related Questions 2 3rd November 2008 20:48
Howto suggestion suse PhP ver 4 + Ver 5 wwparrish Suggest HOWTO 11 7th August 2006 14:29
configuring IPTABLES firewall adityavpratap HOWTO-Related Questions 9 27th May 2006 22:42
High Availability questions sharms HOWTO-Related Questions 3 15th May 2006 17:13
Load balancing on Fedora Care 4 luxpops HOWTO-Related Questions 1 4th April 2006 19:14


All times are GMT +2. The time now is 16:33.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.