We are using haproxy to route traffic to several AWS services that are behind an ELB and noticed the following behavior: - haproxy resolves the ELB address at startup and routes traffic just fine (not sure if haproxy uses the first IP or all resolved IPs and round-robins between them, though) - however, Amazon uses short TTL for ELB DNS entries, 60s or so. If the ELB is modified, due to load, or internal reconfiguration, Amazon can modify the ELB DNS mapping - once the IP(s) mapped to the ELB are completely replaced, relative to the initially resolved ones at startup, haproxy fails to route traffic and returns status 503
Is there a way to configure haproxy to respect DNS TTL when resolving dns names? If not, is there something you can recommend that would allow us to deal with this problem? Our current plan is to stop using DNS for the ELB and instead to use its ip addresses. We'll then periodically do DNS resolutions and once we detect a change, we'll rewrite the configuration and have haproxy reload it. Thanks for you help and for this great product! -aydan
