Hi Charles,
I ran the tcpdump and curl command as well on gateway 1.
curl command gave immediate response, so the server is making calls fine.
But, tcpdump shows interesting picture.
for ex: gateway audit says http routing assertion triggered at 10:15:20 but tcpdump shows that server made the call at 10:15:30
and received at 10:15:30.some milliseconds... but gateway audit says "message processed successfully" at 10:15:35
so gateway audit details shows "Resp time" = 15 seconds
Shall I change the audit level to - Fine, Finer,Finest, would it help ?
Database is external on RDS.
memory/cpu etc on server is very low.
Not sure how to check dns lookup time, but since gateway 2 is on cluster with gateway 1 with same configurations, DNS look up issue would have reflected in gateway 2 as well.. but thats not the case. gateway 2 is fine.
Original Message:
Sent: 01-20-2020 01:24 PM
From: Charles L
Subject: Latency In One Of the Load Balanced CA API Gateway Server
First thought is run a sniffer and see how long it takes, and the handshake.
Is it network side or resource (cpu/memory) is the one with the lag the primary database host? Or does the database reside in rds so its not part of either? If it is local to 1 host and the same host is slower at times it may need more resources since its carrying the load of processing and DB.
And secondly is there dns involved and dns lookup?
If so is it a fixed ip you can add in the system /etc/hosts to rule out any sort of dns lag or modify the route to reference ip VS hostname?
Thanks.
Original Message:
Sent: 01-20-2020 10:18 AM
From: Amit Jaiswal
Subject: Latency In One Of the Load Balanced CA API Gateway Server
Hi All,
I have 2 CA API Gateway servers (similar in configuration) under 1 load balancer.
Server 1 is showing latency (>15seconds) in receiving the response from the backend service.
Latency is happening intermittently ( for example : every 5th or 6th request)
But, Server 2 is not showing such latency in receiving the response from the same backend service.
All the servers and service reside on AWS infrastructure.
Looks like a networking issue, but not sure where is the lag as both servers have same settings and network rules ?
Also, is it worth checking any gateway configuration which could be the cause ? What setting to check ?
Please guide.