Re: Using haproxy and elastic Ips

There is Amazon Cloudfront. There are quite a few clouds on the market - a solution should be cloud-specific not ec2 specific.

Sent from phone.

On Tue Jul 13th, 2010 6:20 PM PDT Dmitri Smirnov wrote:

>I have been reading about haproxy usage in Amazon clouds
>however, but could not find anything related to load distribution
>load between backends that are also in the cloud.
>
>I have been experimenting with uri based consistent hashing
>which haproxy offers.
>
>Haproxy takes backend server names from the config and attempts to
>resolve them right away. Naturally, the cloud backend addresses needs
>be elastic so the stay the same.
>
>However, elastic Ips are not exactly what they seem. While the
>public DNS names and addresses remain the same, for within
>the cloud connections they still resolve to internal 10 dot addresses.
>
>Those can change when instances go up and down. Because haproxy caches the
>actual addresses from the start it presents a problem.
>
>The only solution that I could think of is to have a side cron job that
>would check for the backend addresses change and force haproxy graceful
>restart. This creates an outage window however small.
>
>While haproxy is a old school design that avoids playing with dynamic
>DNS, this is the cloudy reality. It would be nice if there was a way to
>ask haproxy to re-resolve backend entries.
>
>Is there any other solution out there? Am I missing something?
>
>Thanks,
>Dmitri
>
>
       Received on 2010/07/14 06:52