Discussion:
Monitoring IPv6 website
Frank Bulk (iname.com)
2014-08-27 13:31:59 UTC
Permalink
I monitor over 60 IPv6-enabled websites and the only one that's giving me
grief is TWC:

***@nagios:/usr/lib/nagios/plugins# ./check_http -6 -H
www.timewarnercable.com
CRITICAL - Socket timeout after 10 seconds
***@nagios:/usr/lib/nagios/plugins#
***@nagios:/usr/lib/nagios/plugins# ./check_http -6 -H
www.timewarnercable.com -v
GET / HTTP/1.1
User-Agent: check_http/v1.4.15 (nagios-plugins 1.4.15)
Connection: close
Host: www.timewarnercable.com


CRITICAL - Socket timeout after 10 seconds
***@nagios:/usr/lib/nagios/plugins#

Anyone else see this? Why is check_http struggling here, while all other
sites work fine?

Frank
Jens Link
2014-08-27 14:50:04 UTC
Permalink
Post by Frank Bulk (iname.com)
Anyone else see this? Why is check_http struggling here, while all other
sites work fine?
I just tried with telnet and ran tcpdump in another screen "window" looks
like the server does not want to talk to the rest of the world. there is
a TCP handshake but nothing more.

Jens
--
----------------------------------------------------------------------------
| Foelderichstr. 40 | 13595 Berlin, Germany | +49-151-18721264 |
| http://blog.quux.de | jabber: jenslink-l7F9f+FEpVLh7RrbR+***@public.gmane.org | --------------- |
----------------------------------------------------------------------------
Frank Bulk (iname.com)
2014-08-27 15:25:34 UTC
Permalink
Thanks, Jens. But if I drop the "-H" it works fine. What is the difference
between the two checks?

==================================================
***@nagios:/usr/lib/nagios/plugins# ./check_http -6 www.timewarnercable.com
-v
GET / HTTP/1.0
User-Agent: check_http/v1.4.15 (nagios-plugins 1.4.15)
Connection: close


http://www.timewarnercable.com:80/ is 669 characters
STATUS: HTTP/1.1 301 Moved Permanently
**** HEADER ****
Date: Wed, 27 Aug 2014 15:24:41 GMT
Server: Apache
Location: http://business.timewarnercable.com/
Cache-Control: max-age=1800
Expires: Wed, 27 Aug 2014 15:54:41 GMT
Content-Length: 325
Connection: close
Content-Type: text/html; charset=iso-8859-1
Set-Cookie: TWC-COOKIE-webcms-twc-sg=MNEHKIEE; Path=/
**** CONTENT ****
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<html><head>
<title>301 Moved Permanently</title>
</head><body>
<h1>Moved Permanently</h1>
<p>The document has moved <a
href="http://business.timewarnercable.com/">here</a>.</p>
<hr>
<address>Apache Server at webcms-web08.cdp.webapps.rr.com Port 80</address>
</body></html>

HTTP OK: HTTP/1.1 301 Moved Permanently - 669 bytes in 0.100 second response
time |time=0.100085s;;;0.000000 size=669B;;;0
***@nagios:/usr/lib/nagios/plugins#
==================================================

Frank

-----Original Message-----
From: Help [mailto:help-bounces+frnkblk=iname.com-BzZFE/***@public.gmane.org] On
Behalf Of Jens Link
Sent: Wednesday, August 27, 2014 9:50 AM
To: help-BzZFE/***@public.gmane.org
Subject: Re: Monitoring IPv6 website
Post by Frank Bulk (iname.com)
Anyone else see this? Why is check_http struggling here, while all other
sites work fine?
I just tried with telnet and ran tcpdump in another screen "window" looks
like the server does not want to talk to the rest of the world. there is
a TCP handshake but nothing more.

Jens
--
----------------------------------------------------------------------------
| Foelderichstr. 40 | 13595 Berlin, Germany | +49-151-18721264 |
| http://blog.quux.de | jabber: jenslink-l7F9f+FEpVLh7RrbR+***@public.gmane.org | --------------- |

----------------------------------------------------------------------------
Hugo van der Kooij
2014-08-27 13:38:26 UTC
Permalink
This message contains a digitally signed email which can be read by opening the attachment.
Met vriendelijke groet,
With kind regards,




Qi ict

Delftechpark 35-37
Postbus 402, 2600 AK Delft


T : +31 15 888 0 444
F : +31 15 888 0 445
E : mailto:
I : http://www.qi.nl
Frank Bulk
2014-08-29 13:32:32 UTC
Permalink
But there is! Try with a typical webbrowser or wget!

***@nagios:/tmp# wget -6 www.timewarnercable.com
--2014-08-29 08:31:57-- http://www.timewarnercable.com/
Resolving www.timewarnercable.com... 2001:1998:840:b001::7
Connecting to www.timewarnercable.com|2001:1998:840:b001::7|:80...
connected.
HTTP request sent, awaiting response... 301 Moved Permanently
Location: http://www.timewarnercable.com/en/residential.html
[following]
--2014-08-29 08:31:57--
http://www.timewarnercable.com/en/residential.html
Reusing existing connection to www.timewarnercable.com:80.
HTTP request sent, awaiting response... 200 OK
Length: 101218 (99K) [text/html]
Saving to: âindex.htmlâ


100%[=======================================================================
======================================>] 101,218 389K/s in 0.3s

2014-08-29 08:31:58 (389 KB/s) - âindex.htmlâ

***@nagios:/tmp#

So is something broken with check_http?

Regards,

Frank


-----Original Message-----
From: Hugo van der Kooij [mailto:hugo.van.der.kooij-***@public.gmane.org]
Sent: Wednesday, August 27, 2014 8:38 AM
To: Monitoring Plugins Users
Subject: RE: Monitoring IPv6 website

Frank,

Blame them! Ignore them.
But there is simply no HTTP server listening on that IPv6 host.

-----Oorspronkelijk bericht-----
I monitor over 60 IPv6-enabled websites and the only one that's giving me
grief is TWC:

***@nagios:/usr/lib/nagios/plugins# ./check_http -6 -H
www.timewarnercable.com
CRITICAL - Socket timeout after 10 seconds
***@nagios:/usr/lib/nagios/plugins#
***@nagios:/usr/lib/nagios/plugins# ./check_http -6 -H
www.timewarnercable.com -v
GET / HTTP/1.1
User-Agent: check_http/v1.4.15 (nagios-plugins 1.4.15)
Connection: close
Host: www.timewarnercable.com


CRITICAL - Socket timeout after 10 seconds
***@nagios:/usr/lib/nagios/plugins#

Anyone else see this? Why is check_http struggling here, while all other
sites work fine?

Frank
zep
2014-08-29 14:15:22 UTC
Permalink
Post by Frank Bulk
But there is! Try with a typical webbrowser or wget!
--2014-08-29 08:31:57-- http://www.timewarnercable.com/
Resolving www.timewarnercable.com... 2001:1998:840:b001::7
Connecting to www.timewarnercable.com|2001:1998:840:b001::7|:80...
connected.
HTTP request sent, awaiting response... 301 Moved Permanently
---------------------------------------------------^^^^^^^^^^^^^^^
Post by Frank Bulk
Location: http://www.timewarnercable.com/en/residential.html
[following]
--2014-08-29 08:31:57--
http://www.timewarnercable.com/en/residential.html
Reusing existing connection to www.timewarnercable.com:80.
HTTP request sent, awaiting response... 200 OK
Length: 101218 (99K) [text/html]
Saving to: âindex.htmlâ
I think you may have answered your own question.

it would seem to me that check_http only considers http response codes
in the 200 range to be successful and valid, whereas a redirect to a
different server isn't thought to be a successful test/connection.
I'd have to play with some web servers to confirm that notion
Frank Bulk
2014-08-29 17:56:21 UTC
Permalink
I tested that theory a few months ago, but alas, that's not it, as 301 does
work just fine for www.qwest.com, but not for www.timerwarnercable.com

***@nagios:/usr/lib/nagios/plugins# ./check_http -6 -H www.qwest.com
HTTP OK: HTTP/1.1 301 Moved Permanently - 589 bytes in 0.163 second response
time |time=0.163363s;;;0.000000 size=589B;;;0
***@nagios:/usr/lib/nagios/plugins#
***@nagios:/usr/lib/nagios/plugins# ./check_http -6 -H
www.timewarnercable.com
CRITICAL - Socket timeout after 10 seconds
***@nagios:/usr/lib/nagios/plugins#

We may need a NAGIOS developer who understands the check_http code to chime
in.

Regards,

Frank

-----Original Message-----
From: Help [mailto:help-bounces+frnkblk=iname.com-BzZFE/***@public.gmane.org] On
Behalf Of zep
Sent: Friday, August 29, 2014 9:15 AM
To: help-BzZFE/***@public.gmane.org
Subject: Re: Monitoring IPv6 website
Post by Frank Bulk
But there is! Try with a typical webbrowser or wget!
--2014-08-29 08:31:57-- http://www.timewarnercable.com/
Resolving www.timewarnercable.com... 2001:1998:840:b001::7
Connecting to www.timewarnercable.com|2001:1998:840:b001::7|:80...
connected.
HTTP request sent, awaiting response... 301 Moved Permanently
---------------------------------------------------^^^^^^^^^^^^^^^
Post by Frank Bulk
Location: http://www.timewarnercable.com/en/residential.html
[following]
--2014-08-29 08:31:57--
http://www.timewarnercable.com/en/residential.html
Reusing existing connection to www.timewarnercable.com:80.
HTTP request sent, awaiting response... 200 OK
Length: 101218 (99K) [text/html]
Saving to: âindex.htmlâ
I think you may have answered your own question.

it would seem to me that check_http only considers http response codes
in the 200 range to be successful and valid, whereas a redirect to a
different server isn't thought to be a successful test/connection.
I'd have to play with some web servers to confirm that notion
zep
2014-08-29 18:14:00 UTC
Permalink
curiouser and curiouser..

[***@deathstar plugins]# ./check_http -6 www.qwest.com -v
GET / HTTP/1.0
User-Agent: check_http/v1.4.16 (nagios-plugins 1.4.16)
Connection: close


http://www.qwest.com:80/ is 376 characters
STATUS: HTTP/1.1 200 OK
**** HEADER ****
Date: Fri, 29 Aug 2014 18:08:02 GMT
Server: Apache
Set-Cookie: TLTSID=6A8055762FA7102F007B8441495A6D11; Path=/
HostName: vlamardmzpd24.centurytel.com
Accept-Ranges: bytes
Cache-Control: max-age=0
Expires: Fri, 29 Aug 2014 18:08:02 GMT
Vary: Accept-Encoding,User-Agent
Content-Length: 17
Connection: close
Content-Type: text/html
**** CONTENT ****
Hello from .42!

HTTP OK: HTTP/1.1 200 OK - 376 bytes in 0.174 second response time
|time=0.173939s;;;0.000000 size=376B;;;0
[***@deathstar plugins]# ./check_http -6 -H www.qwest.com -v
GET / HTTP/1.1
User-Agent: check_http/v1.4.16 (nagios-plugins 1.4.16)
Connection: close
Host: www.qwest.com


http://www.qwest.com:80/ is 589 characters
STATUS: HTTP/1.1 301 Moved Permanently
**** HEADER ****
Date: Fri, 29 Aug 2014 18:08:08 GMT
Server: Apache
Set-Cookie: TLTSID=6E8BAB5C2FA7102F0019ED7BCA66AF5C; Path=/;
Domain=.qwest.com
HostName: vlamardmzpd24.centurytel.com
Location: http://www.centurylink.com/
Vary: Accept-Encoding
Content-Length: 235
Connection: close
Content-Type: text/html; charset=iso-8859-1
**** CONTENT ****
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<html><head>
<title>301 Moved Permanently</title>
</head><body>
<h1>Moved Permanently</h1>
<p>The document has moved <a
href="http://www.centurylink.com/">here</a>.</p>
</body></html>

HTTP OK: HTTP/1.1 301 Moved Permanently - 589 bytes in 0.179 second
response time |time=0.178524s;;;0.000000 size=589B;;;0

301 for a -H and 200 for a regular request. clearly one is doing it
quite differently from the other... not sure which is the 'right' way.
Post by Frank Bulk
I tested that theory a few months ago, but alas, that's not it, as 301 does
work just fine for www.qwest.com, but not for www.timerwarnercable.com
HTTP OK: HTTP/1.1 301 Moved Permanently - 589 bytes in 0.163 second response
time |time=0.163363s;;;0.000000 size=589B;;;0
www.timewarnercable.com
CRITICAL - Socket timeout after 10 seconds
We may need a NAGIOS developer who understands the check_http code to chime
in.
Regards,
Frank
-----Original Message-----
Behalf Of zep
Sent: Friday, August 29, 2014 9:15 AM
Subject: Re: Monitoring IPv6 website
Post by Frank Bulk
But there is! Try with a typical webbrowser or wget!
--2014-08-29 08:31:57-- http://www.timewarnercable.com/
Resolving www.timewarnercable.com... 2001:1998:840:b001::7
Connecting to www.timewarnercable.com|2001:1998:840:b001::7|:80...
connected.
HTTP request sent, awaiting response... 301 Moved Permanently
---------------------------------------------------^^^^^^^^^^^^^^^
Post by Frank Bulk
Location: http://www.timewarnercable.com/en/residential.html
[following]
--2014-08-29 08:31:57--
http://www.timewarnercable.com/en/residential.html
Reusing existing connection to www.timewarnercable.com:80.
HTTP request sent, awaiting response... 200 OK
Length: 101218 (99K) [text/html]
Saving to: âindex.htmlâ
I think you may have answered your own question.
it would seem to me that check_http only considers http response codes
in the 200 range to be successful and valid, whereas a redirect to a
different server isn't thought to be a successful test/connection.
I'd have to play with some web servers to confirm that notion
Frank Bulk (iname.com)
2014-08-29 18:24:29 UTC
Permalink
So it looks like the -H makes it a HTTP/1.1 request.

So my theory was that HTTP/1.1 requests make www.timewarnercable.com choke,
but 1.1 requests work fine with curl and wget.


***@nagios:/usr/lib/nagios/plugins# ./check_http -H www.timewarnercable.com
-v
GET / HTTP/1.1
User-Agent: check_http/v1.4.15 (nagios-plugins 1.4.15)
Connection: close
Host: www.timewarnercable.com


CRITICAL - Socket timeout after 10 seconds
***@nagios:/usr/lib/nagios/plugins# curl -v -1 www.timewarnercable.com
* About to connect() to www.timewarnercable.com port 80 (#0)
* Trying 2001:1998:840:b001::7... connected
* Connected to www.timewarnercable.com (2001:1998:840:b001::7) port 80 (#0)
Post by Frank Bulk (iname.com)
GET / HTTP/1.1
User-Agent: curl/7.21.0 (x86_64-pc-linux-gnu) libcurl/7.21.0
OpenSSL/0.9.8o zlib/1.2.3.4 libidn/1.15 libssh2/1.2.5
Post by Frank Bulk (iname.com)
Host: www.timewarnercable.com
Accept: */*
< HTTP/1.1 301 Moved Permanently
< Date: Fri, 29 Aug 2014 18:22:50 GMT
< Server: Apache
< Location: http://www.timewarnercable.com/en/residential.html
< Cache-Control: max-age=1800
< Expires: Fri, 29 Aug 2014 18:52:50 GMT
< Content-Length: 331
< Keep-Alive: timeout=10, max=586
< Connection: Keep-Alive
< Content-Type: text/html; charset=iso-8859-1
< Set-Cookie: TWC-COOKIE-webcms-twc-sg=BPEGKIEE; Path=/
<
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<html><head>
<title>301 Moved Permanently</title>
</head><body>
<h1>Moved Permanently</h1>
<p>The document has moved <a
href="http://www.timewarnercable.com/en/residential.html">here</a>.</p>
<hr>
<address>Apache Server at www.timewarnercable.com Port 80</address>
</body></html>
* Connection #0 to host www.timewarnercable.com left intact
* Closing connection #0
***@nagios:/usr/lib/nagios/plugins#
***@nagios:/usr/lib/nagios/plugins# wget -6 -vvvv www.timewarnercable.com
--2014-08-29 13:23:45-- http://www.timewarnercable.com/
Resolving www.timewarnercable.com... 2001:1998:840:b001::7
Connecting to www.timewarnercable.com|2001:1998:840:b001::7|:80...
connected.
HTTP request sent, awaiting response... 301 Moved Permanently
Location: http://www.timewarnercable.com/en/residential.html [following]
--2014-08-29 13:23:45-- http://www.timewarnercable.com/en/residential.html
Reusing existing connection to www.timewarnercable.com:80.
HTTP request sent, awaiting response... 200 OK
Length: 101218 (99K) [text/html]
Saving to: âindex.html.3â

100%[=======================================================================
==================================>] 101,218 --.-K/s in 0.09s

2014-08-29 13:23:46 (1.03 MB/s) - âindex.html.3â

***@nagios:/usr/lib/nagios/plugins#


Frank

-----Original Message-----
From: Help [mailto:help-bounces+frnkblk=iname.com-BzZFE/***@public.gmane.org] On
Behalf Of zep
Sent: Friday, August 29, 2014 1:14 PM
To: help-BzZFE/***@public.gmane.org
Subject: Re: Monitoring IPv6 website


curiouser and curiouser..

[***@deathstar plugins]# ./check_http -6 www.qwest.com -v
GET / HTTP/1.0
User-Agent: check_http/v1.4.16 (nagios-plugins 1.4.16)
Connection: close


http://www.qwest.com:80/ is 376 characters
STATUS: HTTP/1.1 200 OK
**** HEADER ****
Date: Fri, 29 Aug 2014 18:08:02 GMT
Server: Apache
Set-Cookie: TLTSID=6A8055762FA7102F007B8441495A6D11; Path=/
HostName: vlamardmzpd24.centurytel.com
Accept-Ranges: bytes
Cache-Control: max-age=0
Expires: Fri, 29 Aug 2014 18:08:02 GMT
Vary: Accept-Encoding,User-Agent
Content-Length: 17
Connection: close
Content-Type: text/html
**** CONTENT ****
Hello from .42!

HTTP OK: HTTP/1.1 200 OK - 376 bytes in 0.174 second response time
|time=0.173939s;;;0.000000 size=376B;;;0
[***@deathstar plugins]# ./check_http -6 -H www.qwest.com -v
GET / HTTP/1.1
User-Agent: check_http/v1.4.16 (nagios-plugins 1.4.16)
Connection: close
Host: www.qwest.com


http://www.qwest.com:80/ is 589 characters
STATUS: HTTP/1.1 301 Moved Permanently
**** HEADER ****
Date: Fri, 29 Aug 2014 18:08:08 GMT
Server: Apache
Set-Cookie: TLTSID=6E8BAB5C2FA7102F0019ED7BCA66AF5C; Path=/;
Domain=.qwest.com
HostName: vlamardmzpd24.centurytel.com
Location: http://www.centurylink.com/
Vary: Accept-Encoding
Content-Length: 235
Connection: close
Content-Type: text/html; charset=iso-8859-1
**** CONTENT ****
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<html><head>
<title>301 Moved Permanently</title>
</head><body>
<h1>Moved Permanently</h1>
<p>The document has moved <a
href="http://www.centurylink.com/">here</a>.</p>
</body></html>

HTTP OK: HTTP/1.1 301 Moved Permanently - 589 bytes in 0.179 second
response time |time=0.178524s;;;0.000000 size=589B;;;0

301 for a -H and 200 for a regular request. clearly one is doing it
quite differently from the other... not sure which is the 'right' way.
Post by Frank Bulk (iname.com)
I tested that theory a few months ago, but alas, that's not it, as 301
does
Post by Frank Bulk (iname.com)
work just fine for www.qwest.com, but not for www.timerwarnercable.com
HTTP OK: HTTP/1.1 301 Moved Permanently - 589 bytes in 0.163 second
response
Post by Frank Bulk (iname.com)
time |time=0.163363s;;;0.000000 size=589B;;;0
www.timewarnercable.com
CRITICAL - Socket timeout after 10 seconds
We may need a NAGIOS developer who understands the check_http code to
chime
Post by Frank Bulk (iname.com)
in.
Regards,
Frank
-----Original Message-----
On
Post by Frank Bulk (iname.com)
Behalf Of zep
Sent: Friday, August 29, 2014 9:15 AM
Subject: Re: Monitoring IPv6 website
Post by Frank Bulk
But there is! Try with a typical webbrowser or wget!
--2014-08-29 08:31:57-- http://www.timewarnercable.com/
Resolving www.timewarnercable.com... 2001:1998:840:b001::7
Connecting to www.timewarnercable.com|2001:1998:840:b001::7|:80...
connected.
HTTP request sent, awaiting response... 301 Moved Permanently
---------------------------------------------------^^^^^^^^^^^^^^^
Post by Frank Bulk
Location: http://www.timewarnercable.com/en/residential.html
[following]
--2014-08-29 08:31:57--
http://www.timewarnercable.com/en/residential.html
Reusing existing connection to www.timewarnercable.com:80.
HTTP request sent, awaiting response... 200 OK
Length: 101218 (99K) [text/html]
Saving to: âindex.htmlâ
I think you may have answered your own question.
it would seem to me that check_http only considers http response codes
in the 200 range to be successful and valid, whereas a redirect to a
different server isn't thought to be a successful test/connection.
I'd have to play with some web servers to confirm that notion
Jim Welch
2014-08-29 18:26:33 UTC
Permalink
Try using the '-f' parameter to control whether or not check_http stops
at the first redirect or
follows the redirect and checks the resulting page.

-f ok
-f follow

(check_http -h for details)
Post by zep
curiouser and curiouser..
Frank Bulk (iname.com)
2014-08-29 18:30:21 UTC
Permalink
Sorry, no change.

***@nagios:/usr/lib/nagios/plugins# ./check_http -H www.timewarnercable.com
-v -f follow
option f:4
GET / HTTP/1.1
User-Agent: check_http/v1.4.15 (nagios-plugins 1.4.15)
Connection: close
Host: www.timewarnercable.com


CRITICAL - Socket timeout after 10 seconds
***@nagios:/usr/lib/nagios/plugins# ./check_http -H www.timewarnercable.com
-v -f ok
option f:0
GET / HTTP/1.1
User-Agent: check_http/v1.4.15 (nagios-plugins 1.4.15)
Connection: close
Host: www.timewarnercable.com


CRITICAL - Socket timeout after 10 seconds
***@nagios:/usr/lib/nagios/plugins#

Frank

-----Original Message-----
From: Help [mailto:help-bounces+frnkblk=iname.com-BzZFE/***@public.gmane.org] On
Behalf Of Jim Welch
Sent: Friday, August 29, 2014 1:27 PM
To: Monitoring Plugins Users
Subject: Re: Monitoring IPv6 website

Try using the '-f' parameter to control whether or not check_http stops
at the first redirect or
follows the redirect and checks the resulting page.

-f ok
-f follow

(check_http -h for details)
Post by zep
curiouser and curiouser..
Loading...