Hi,
Le 31/01/2018 à 03:00, flamese...@yahoo.co.jp a écrit :
Hello,
What exactly does option redispatch do?
It gives a chance to retry on another server if the connection can't be
established on the one chosen by the loadbalancing algorithm. It's
important to understand that it concerns only the connection
establishment step. See below for details.
I have a haproxy in front of two web servers, if one web server get
killed when haproxy is forwarding a request to that server,
will this request get re-forwarded to another server?
So I had an test.
In one server, I run
ruby -run -ehttpd . -p8001
and
ruby -run -ehttpd . -p8000
and i start haproxy
then do a ab
ab -n 20000 -c 10 http://127.0.0.1:8080/
while the ab is running, I killed 8001 ruby, then after some time I
started it again.
here is the ab result:
Complete requests: 20000
Failed requests: 5
(Connect: 0, Receive: 0, Length: 5, Exceptions: 0)
And haproxy.log
grep -c GET haproxy.log
20000
grep GET haproxy.log | grep -v 200
Jan 31 10:48:12 localhost haproxy[5948]: 127.0.0.1:45516
[31/Jan/2018:10:48:12.386] web1 app1/b 0/0/0/-1/5 -1 0 - - SD--
10/10/8/3/0 0/0 "GET / HTTP/1.0"
Jan 31 10:48:12 localhost haproxy[5948]: 127.0.0.1:45538
[31/Jan/2018:10:48:12.391] web1 app1/b 0/0/1/-1/1 -1 0 - - SD--
10/10/8/4/0 0/0 "GET / HTTP/1.0"
Jan 31 10:48:12 localhost haproxy[5948]: 127.0.0.1:45528
[31/Jan/2018:10:48:12.389] web1 app1/b 0/0/1/-1/3 -1 0 - - SD--
9/9/8/3/0 0/0 "GET / HTTP/1.0"
Jan 31 10:48:12 localhost haproxy[5948]: 127.0.0.1:45524
[31/Jan/2018:10:48:12.388] web1 app1/b 0/0/1/-1/4 -1 0 - - SD--
8/8/7/2/0 0/0 "GET / HTTP/1.0"
Jan 31 10:48:12 localhost haproxy[5948]: 127.0.0.1:45544
[31/Jan/2018:10:48:12.392] web1 app1/b 0/0/0/-1/1 -1 0 - - SD--
7/7/6/0/0 0/0 "GET / HTTP/1.0"
Here, your logs indicate that the connection was already established and
the request was also already sent to the server app1/b, but the
connection was dropped in the middle (the server was stopped in the
middle as you previously said). It's too late to redispatch a
connection, so the behaviour is expected.
Here is the config:
global
maxconn 5000
log 127.0.0.1 local2 debug
daemon
defaults
log global
option httplog
retries 3
option redispatch
timeout client 30s
timeout connect 30s
timeout server 30s
timeout http-request 30s
timeout http-keep-alive 30s
frontend web1
bind *:8080
mode http
default_backend app1
backend app1
balance roundrobin
mode http
server a 127.0.0.1:8000 check
server b 127.0.0.1:8001 check
I have tried v1.8.3 and v1.7.10
And I missing something?
Thanks
--
Cyril Bonté
