[CentOS] clustering and load balancing Apache

[Sergej Kandyla]

Florin Andrei пишет:
> Sergej Kandyla wrote:
>   
>> apache is good as backend server for dynamic applications.
>> You could use something like nginx, haproxy as frontend for balancing 
>> multiple backend servers.
>> I'm using nginx. This light web server could serve many thousand 
>> concurrent connections! It works great!
>>     
>
> In addition to the user-space solutions mentioned above, there are also 
> kernel-level solutions, such as Linux Virtual Server, or LVS:
>
> http://www.linuxvirtualserver.org/
>   

IMHO it's not right compare light web server with Virtual servers.

Look at http://www.linuxvirtualserver.org/whatis.html
In this scheme you could naturally use nginx as loadbalancer on the Load 
Balancer Linux Box.

Also "The mission of the project is to build a high-performance and 
highly available server for Linux using clustering 
<http://en.wikipedia.org/wiki/Computer_cluster> technology, which 
provides good scalability, reliability and serviceability."

If you need high-availability you could also use XEN\KVM or OpenVZ. 
These technologies are actively developing... XEN\KVM are supported 
natively in the RHEL\Centos kernel.
I'm prefer OpenVZ as light-weight virtualization.
http://wiki.openvz.org/HA_cluster_with_DRBD_and_Heartbeat

> I am under the impression that, speaking in general, user-space 
> balancers provide more features (are smarter), while the kernel-space 
> ones are faster (provide more in terms of raw speed and max load). I 
> could be wrong.
>
> Can anybody provide a performance comparison between, say, nginx and 
> LVS? (max connections, max new connections rate, max bandwidth, max 
> packets per second, etc.)
>
>