Hi
On 30.08.2016 09:11, Baptiste wrote:
The way we designed the feature is more like a "server template" line which
may be used to pre-configure in memory X servers sharing the same DNS
resolution.
In your case X=2. If you intend to have up to 10 servers for this service,
simply set X to 10.
HAProxy will use A records to create the servers and the health checks will
ensure that the servers are available before sending them traffic.
If a A record disappear from the response, the corresponding server will
get down. If a new server is added and we provisioned less than X, then a
new server is provisioned.
This X "upper" limit is to ensure compatibility with all HAProxy features
(such as hash LBing algorithms).
Could you let me know if that meets your requirements?
(we can still change this description).
What would happen if I'd configure X = 2 and the following happens:
1. Initially only 127.0.0.1 is returned.
2. 127.0.0.2 is added and healthy.
3. 127.0.0.1 is removed from DNS and thus marked DOWN.
4. 127.0.0.3 is added (with 127.0.0.2 still being healthy and 127.0.0.1
still being DOWN / missing from the DNS response)
You said that once an IP address disappears the backend will be marked
as DOWN and that there is an upper limit. Are new IP addresses able to
push removed IP addresses from the list or will removed IP addresses be
DOWN and taking up a slot until they reappear?
If new IPs are able to push away old IPs it sounds like it will meet my
requirements perfectly. I won't have control over the IP addresses
assigned in the DNS.
Thanks for your replies so far! Looking forward to it.
Best regards
Tim Düsterhus
