Re: dns resoluton and caching
On Wed, Jul 2, 2014 at 5:03 AM, Yumerefendi, Aydan aydan.yumerefe...@inin.com wrote: 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 Hi, This is not yet available in HAProxy. It's a common request and should be available some day, but no idea when! Baptiste
Re: dns resoluton and caching
Thank you Baptiste. I think it will be very useful feature to add for any service that uses dynamic dns of some sort. Thanks for your reply, Best, ‹aydan On 7/3/14, 4:41 PM, Baptiste bed...@gmail.com wrote: On Wed, Jul 2, 2014 at 5:03 AM, Yumerefendi, Aydan aydan.yumerefe...@inin.com wrote: 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 Hi, This is not yet available in HAProxy. It's a common request and should be available some day, but no idea when! Baptiste
dns resoluton and caching
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
