Trouble starting haproxy on Debian8 (systemd)

[SL]

Hi,

Today I cloned a server which is running haproxy 1.6 on a debian8 server
without problems.  However, for some reason the clone refuses to start
haproxy (IPs and hostname have been updated of course).

Probably I'm missing something simple, but I can't think what it is.  I
have very little experience with systemd, so am now at a loss as to what's
wrong. I'm hoping someone here might be able to suggest something...


Nov 16 15:25:50 x systemd[1]: Starting HAProxy Load Balancer...
Nov 16 15:25:50 x systemd[1]: haproxy.service: control process exited,
code=exited status=2
Nov 16 15:25:50 x systemd[1]: Failed to start HAProxy Load Balancer.
Nov 16 15:25:50 x systemd[1]: Unit haproxy.service entered failed state.
Nov 16 15:25:51 x sudo[3843]: pam_unix(sudo:session): session closed
for user root
Nov 16 15:25:51 x systemd[1]: haproxy.service holdoff time over,
scheduling restart.
Nov 16 15:25:51 x systemd[1]: Stopping HAProxy Load Balancer...
Nov 16 15:25:51 x systemd[1]: Starting HAProxy Load Balancer...
Nov 16 15:25:51 x systemd[1]: haproxy.service: control process exited,
code=exited status=2
Nov 16 15:25:51 x systemd[1]: Failed to start HAProxy Load Balancer.
Nov 16 15:25:51 x systemd[1]: Unit haproxy.service entered failed state.
Nov 16 15:25:51 x systemd[1]: haproxy.service holdoff time over,
scheduling restart.
Nov 16 15:25:51 x systemd[1]: Stopping HAProxy Load Balancer...
Nov 16 15:25:51 x systemd[1]: Starting HAProxy Load Balancer...
Nov 16 15:25:51 x systemd[1]: haproxy.service: control process exited,
code=exited status=2
Nov 16 15:25:51 x systemd[1]: Failed to start HAProxy Load Balancer.
Nov 16 15:25:51 x systemd[1]: Unit haproxy.service entered failed state.
Nov 16 15:25:51 x systemd[1]: haproxy.service holdoff time over,
scheduling restart.
Nov 16 15:25:51 x systemd[1]: Stopping HAProxy Load Balancer...
Nov 16 15:25:51 x systemd[1]: Starting HAProxy Load Balancer...
Nov 16 15:25:51 x systemd[1]: haproxy.service: control process exited,
code=exited status=2
Nov 16 15:25:51 x systemd[1]: Failed to start HAProxy Load Balancer.
Nov 16 15:25:51 x systemd[1]: Unit haproxy.service entered failed state.
Nov 16 15:25:51 x systemd[1]: haproxy.service holdoff time over,
scheduling restart.
Nov 16 15:25:51 x systemd[1]: Stopping HAProxy Load Balancer...
Nov 16 15:25:51 x systemd[1]: Starting HAProxy Load Balancer...
Nov 16 15:25:51 x systemd[1]: haproxy.service: control process exited,
code=exited status=2
Nov 16 15:25:51 x systemd[1]: Failed to start HAProxy Load Balancer.
Nov 16 15:25:51 x systemd[1]: Unit haproxy.service entered failed state.
Nov 16 15:25:52 x systemd[1]: haproxy.service holdoff time over,
scheduling restart.
Nov 16 15:25:52 x systemd[1]: Stopping HAProxy Load Balancer...
Nov 16 15:25:52 x systemd[1]: Starting HAProxy Load Balancer...
Nov 16 15:25:52 x systemd[1]: haproxy.service start request repeated
too quickly, refusing to start.
Nov 16 15:25:52 x systemd[1]: Failed to start HAProxy Load Balancer.
Nov 16 15:25:52 x systemd[1]: Unit haproxy.service entered failed state.
Nov 16 15:29:25 x systemd[1]: Starting Cleanup of Temporary
Directories...

If I try  /etc/init.d/haproxy start, then I get:


[] Starting haproxy (via systemctl): haproxy.serviceJob for
haproxy.service failed. See 'systemctl status haproxy.service' and
'journalctl -xn' for details

journalctl -xn returns 'No journal files were found.'

 'systemctl status haproxy.service' returns:

 haproxy.service - HAProxy Load Balancer
   Loaded: loaded (/lib/systemd/system/haproxy.service; enabled)
   Active: failed (Result: start-limit) since Mon 2015-11-16 15:49:27 GMT;
1min 39s ago
 Docs: man:haproxy(1)
   file:/usr/share/doc/haproxy/configuration.txt.gz
  Process: 3751 ExecStartPre=/usr/local/sbin/haproxy -f ${CONFIG} -c -q
(code=exited, status=2)



Any ideas about where to go from here?

Thank you!

Re: appsession replacement in 1.6

[Sylvain Faivre]

Hi Aleks,

On 11/10/2015 10:56 PM, Aleksandar Lazic wrote:

Dear Sylvain Faivre,

Am 10-11-2015 12:48, schrieb Sylvain Faivre:

On 11/10/2015 12:00 AM, Aleksandar Lazic wrote:

Hi Sylvain Faivre.

Am 09-11-2015 17:31, schrieb Sylvain Faivre:


[snipp]


So, I've got this so far :

backend http

  stick-table type string len 24 size 10m expire 1h peers prod

  stick on urlp(JSESSIONID,;)
  stick on cookie(JSESSIONID)


Does this seem right ?
The help for "stick on" tells it defines a request pattern, so I guess
this would not match JSESSIONID cookie ou url parameter set in the
reply ?


I have no java server here to test this commands but with this commands
haproxy does not warn you about some config errors ;-).

###
backend dest01
   mode http

   stick-table type string len 24 size 10m expire 1h peers prod

   stick on urlp(JSESSIONID,;)
   stick on cookie(JSESSIONID)

   stick store-response cookie(JSESSIONID)
#  stick store-response res.hdr(JSESSIONID,;)

   stick store-request cookie(JSESSIONID)
   stick store-request urlp(JSESSIONID,;)

   server srv_dest01 dest01.com:80
###

I have not seen a good option to read the JSESSIONID from the response
header in case it is not in a cookie.
Have anyone I idea?!

Please can you post a full response header which was created from the
app or appserver when the app or appserver have detected that the client
does not allow cookies.


[snipp]


In fact, the server sends the JSESSIONID as a cookie even if the
client does not support cookies, *and* it adds the JSESSIONID as a URL
parameter in all links, so this should be all right.


This would be helpfully to see the full response.
Maybe some appserver behaves different.


As far as I know, there is no way for the server to detect if the client 
has cookies enabled, by looking only at the first request from that client.


According to a quick Google search, the most common ways to detect 
cookies support are either to use Javascript (so client-side check) or 
to reply with a redirect response with the cookie set, then when 
processing the redirected URL, check if the client sent the cookie along 
with the request (so this case will be covered by the proposed HAproxy 
settings).


I don't feel comfortable giving our application server version on a 
public list, but I will send it to you in private.


Here are the headers from a client request and server reply, with a 
brand new profile on the client (with cookies disabled) :


- request :
GET /front/url1.do?m=booking=FR HTTP/1.1
Host: redacted.host.domain
User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:42.0) 
Gecko/20100101 Firefox/42.0

Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
Connection: keep-alive

- reply :
HTTP/1.1 200 OK
Date: Mon, 16 Nov 2015 15:25:41 GMT
Content-Type: text/html;charset=ISO-8859-15
Set-Cookie: JSESSIONID=uNmYNvgUME5-8LYPzimsCg__.8d15fc; Path=/front
Vary: Accept-Encoding
Content-Encoding: gzip
Transfer-Encoding: chunked

And here is a URL sample from the body of the reply. You will notice 
that the jsessionid is there twice, first one after a semicolon and 
second one after a question mark. I am not sure if this comes from the 
application server of from our custom code.


src="https://redacted.host.domain/front/url2.do;jsessionid=uNmYNvgUME5-8LYPzimsCg__.8d15fc?jsessionid=uNmYNvgUME5-8LYPzimsCg__.8d15fc&langcode=FR"; 
language="JavaScript">






I just tried your config on a test server, and the session IDs are
rightly recorded in the table, whether the client accepts cookies or
not.


Perfect.


I still have some test cases to run, I will check this next week and
report back if needed.


Oh yes please tell us the results so that we can add this as migration
example for appsession.


OK, I will. This will not go into production yet, we still need to run 
it on a test environment for at least 3 weeks...


Best regards.
Sylvain