[SOLVED] Emby bad request for ip6 address with nagios

hoes · 12-31-2016, 07:32 AM

I have nagios 4.0.8 (and nagios-plugins at 2.0.3) running which checks emby that is running on the same computer (CentOS).
I use the following command to check the emby server:

Code:

/lib64/nagios/plugins/check_http -I 127.0.0.1 -p 8096

When I run this with the verbose flag -v I get the following result:

Code:

GET / HTTP/1.0
User-Agent: check_http/v2.0.3 (nagios-plugins 2.0.3)
Connection: close
Accept: */*


http://127.0.0.1:8096/ is 235 characters
STATUS: HTTP/1.1 400 Bad Request
**** HEADER ****
Content-Type: text/html; charset=utf-8
Server: Mono-HTTPAPI/1.0
Date: Sat, 31 Dec 2016 13:10:50 GMT
Content-Length: 65
Connection: close
**** CONTENT ****
<h1>Bad Request (Invalid url: http://::ffff:127.0.0.1:8096/)</h1>
HTTP WARNING: HTTP/1.1 400 Bad Request - 235 bytes in 0.001 second response time |time=0.001292s;;;0.000000 size=235B;;;0

I get exactly the same result if I add the -4 flag for ip4 addresses.
Curl results are similar.

Emby works fine if I direct my browser to 127.0.0.1:8096.

The problem seems to be that emby does not handle the url http://::ffff:127.0.0.1:8096/ well.

Is it likely that something is wrong with emby?
Or is something wrong with ip6 configuration?

I would be very interested in any suggestions to tackle this problem

Habitual · 12-31-2016, 09:57 AM

Apache Virtualhost and/or /etc/hosts would be my first guess.
I'm gonna say what I think I know and we'll see.

::ffff:127.0.0.1 is 2 identifiers.
127 is obvious localhost for ipv4
but :ffff may be localhost for ipv6?

Anyone? Hope this doesn't hurt.

Yeah, that doesn't bear out. I can only say I don't know.

But someone does, stick around.

Cheers in 2017

Edit: Sat Dec 31, 2016 - 11:19:38 AM EST
My revised guess is the check_http plugin can't handle what Emby is throwing back.

hoes · 01-04-2017, 01:57 PM

Thanks for your suggestions.
I have had a look at my nagios data.
It seems that the problem was introduced on 19 December while installing emby 3.1.0-9.1.

c0wb0y · 01-04-2017, 02:42 PM

How about explicitly config Emby to listen only to ipv4?

hoes · 01-06-2017, 12:26 PM

I'd love to try to set it to ipv4.
Do you know if/where this can be changed?

hoes · 01-06-2017, 01:22 PM

Okay, so I disabled ipv6

Code:

> sysctl net.ipv6.conf.default.disable_ipv6
net.ipv6.conf.default.disable_ipv6 = 1

However, I still get the same response from check_http including the <h1>Bad Request (Invalid url: http://::ffff:127.0.0.1:8096/)</h1> bit.

hoes · 01-08-2017, 10:26 AM

Thanks for all your suggestions.
I found the answer.
It seems that Emby would like to have a Host: field in the http request.
I tried to add this using the -k and --header flags of check_http, but this was not successfully parsed.
Therefore I specified the IP as a host (-H):

Code:

/lib64/nagios/plugins/check_http -H 127.0.0.1 -p 8096

This worked and I reenabled ipv6.

Habitual · 01-08-2017, 04:09 PM

Good job and well done!