# Check\_http 400 and 404 for popular websites

**URL:** <https://community.icinga.com/t/check-http-400-and-404-for-popular-websites/12288>\
**Category:** Icinga 2\
**Created:** [July 6, 2023, 4:33pm UTC](https://community.icinga.com/t/check-http-400-and-404-for-popular-websites/12288 "2023-07-06T16:33:32Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![eimrek](https://community.icinga.com/user_avatar/community.icinga.com/eimrek/32/6905_2.png) [@eimrek](https://community.icinga.com/u/eimrek)\
**Post date:** [July 6, 2023, 4:33pm UTC](https://community.icinga.com/t/check-http-400-and-404-for-popular-websites/12288/1 "2023-07-06T16:33:33Z")

</div>

Hi! I need checks for external links on my website and I’m running into problems with check\_http for some websites.

See these examples:

1. [www.nature.com](http://www.nature.com), gives 400 Bad Request

```auto
$ check_http -I www.nature.com -v                                 
GET / HTTP/1.0
User-Agent: check_http/v2.2 (monitoring-plugins 2.2)
Connection: close

http://www.nature.com:80/ is 694 characters
STATUS: HTTP/1.1 400 Bad Request
****HEADER****
Connection: close
Content-Length: 273
Content-Type: text/html; charset=UTF-8
Referrer-Policy: no-referrer
X-Cdn-Origin: SNPaaS
Accept-Ranges: bytes
Date: Thu, 06 Jul 2023 16:12:21 GMT
Via: 1.1 varnish
X-Served-By: cache-fra-eddf8230033-FRA
X-Cache: MISS
X-Cache-Hits: 0
X-Timer: S1688659941.052221,VS0,VE102
alt-svc: h3=":443";ma=86400,h3-29=":443";ma=86400,h3-27=":443";ma=86400
****CONTENT****
<html><head>
<meta http-equiv="content-type" content="text/html;charset=utf-8">
<title>400 Bad Request</title>
</head>
<body text=#000000 bgcolor=#ffffff>
<h1>Error: Bad Request</h1>
<h2>Your client has issued a malformed or illegal request.</h2>
<h2></h2>
</body></html>

HTTP WARNING: HTTP/1.1 400 Bad Request - 694 bytes in 0.125 second response time |time=0.124696s;;;0.000000;10.000000 size=694B;;;0

```

1. www.snf.ch, gives 404 Not Found

```auto
$ check_http -I www.snf.ch -v
GET / HTTP/1.0
User-Agent: check_http/v2.2 (monitoring-plugins 2.2)
Connection: close

http://www.snf.ch:80/ is 274 characters
STATUS: HTTP/1.1 404 Not Found
****HEADER****
Date: Thu, 06 Jul 2023 16:15:26 GMT
Content-Type: text/html
Content-Length: 146
Connection: close
****CONTENT****
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx</center>
</body>
</html>

HTTP WARNING: HTTP/1.1 404 Not Found - 274 bytes in 0.013 second response time |time=0.013416s;;;0.000000;10.000000 size=274B;;;0

```

* * *

Version & other environment info:

```auto
$ icinga2 --version
icinga2 - The Icinga 2 network monitoring daemon (version: r2.13.3-1)
$ sudo icinga2 feature list
Disabled features: compatlog elasticsearch gelf graphite icingadb influxdb influxdb2 livestatus opentsdb perfdata statusdata syslog
Enabled features: api checker command debuglog ido-mysql mainlog notification
$ sudo icinga2 daemon -C
[2023-07-06 18:31:26 +0200] information/cli: Icinga application loader (version: r2.13.3-1)
[2023-07-06 18:31:26 +0200] information/cli: Loading configuration file(s).
[2023-07-06 18:31:26 +0200] information/ConfigItem: Committing config item(s).
[2023-07-06 18:31:26 +0200] information/ApiListener: My API identity: stivm0080.epfl.ch
[2023-07-06 18:31:26 +0200] warning/ApplyRule: Apply rule 'backup-downtime' (in /etc/icinga2/conf.d/downtimes.conf: 5:1-5:52) for type 'ScheduledDowntime' does not match anywhere!
[2023-07-06 18:31:26 +0200] warning/ApplyRule: Apply rule 'docker' (in /etc/icinga2/zones.d/master/services.conf: 50:1-50:22) for type 'Service' does not match anywhere!
[2023-07-06 18:31:26 +0200] warning/ApplyRule: Apply rule 'check_dump' (in /etc/icinga2/zones.d/master/services.conf: 176:1-176:26) for type 'Service' does not match anywhere!
[2023-07-06 18:31:26 +0200] information/ConfigItem: Instantiated 1 IcingaApplication.
[2023-07-06 18:31:26 +0200] information/ConfigItem: Instantiated 2 HostGroups.
[2023-07-06 18:31:26 +0200] information/ConfigItem: Instantiated 20 Hosts.
[2023-07-06 18:31:26 +0200] information/ConfigItem: Instantiated 2 NotificationCommands.
[2023-07-06 18:31:26 +0200] information/ConfigItem: Instantiated 283 Notifications.
[2023-07-06 18:31:26 +0200] information/ConfigItem: Instantiated 2 FileLoggers.
[2023-07-06 18:31:26 +0200] information/ConfigItem: Instantiated 1 CheckerComponent.
[2023-07-06 18:31:26 +0200] information/ConfigItem: Instantiated 1 IdoMysqlConnection.
[2023-07-06 18:31:26 +0200] information/ConfigItem: Instantiated 30 Zones.
[2023-07-06 18:31:26 +0200] information/ConfigItem: Instantiated 1 ExternalCommandListener.
[2023-07-06 18:31:26 +0200] information/ConfigItem: Instantiated 1 ApiListener.
[2023-07-06 18:31:26 +0200] information/ConfigItem: Instantiated 28 Endpoints.
[2023-07-06 18:31:26 +0200] information/ConfigItem: Instantiated 1 ApiUser.
[2023-07-06 18:31:26 +0200] information/ConfigItem: Instantiated 248 CheckCommands.
[2023-07-06 18:31:26 +0200] information/ConfigItem: Instantiated 1 NotificationComponent.
[2023-07-06 18:31:26 +0200] information/ConfigItem: Instantiated 9 Users.
[2023-07-06 18:31:26 +0200] information/ConfigItem: Instantiated 9 UserGroups.
[2023-07-06 18:31:26 +0200] information/ConfigItem: Instantiated 3 TimePeriods.
[2023-07-06 18:31:26 +0200] information/ConfigItem: Instantiated 263 Services.
[2023-07-06 18:31:26 +0200] information/ConfigItem: Instantiated 3 ServiceGroups.
[2023-07-06 18:31:26 +0200] information/ScriptGlobal: Dumping variables to file '/var/cache/icinga2/icinga2.vars'
[2023-07-06 18:31:26 +0200] information/cli: Finished validating the configuration file(s).

```

OS: Ubuntu 18.04

* * *

Both of the websites above work well with curl and wget on the same server.

Other websites, such as [www.google.com](http://www.google.com) work well also with check\_http.

I have tried to mess around with all the various options (-f, -A, -S, …) but nothing seems to work. Does anybody have any ideas how to make this work?

Thanks!

---

<div class="post-metadata">

**Author:** ![rsx](https://community.icinga.com/user_avatar/community.icinga.com/rsx/32/2094_2.png) [@rsx](https://community.icinga.com/u/rsx)\
**Post date:** [July 7, 2023, 6:48am UTC](https://community.icinga.com/t/check-http-400-and-404-for-popular-websites/12288/2 "2023-07-07T06:48:21Z")

</div>

You are trying to test via

```auto
-I, --IP-address=ADDRESS
    IP address or name (use numeric address if possible to bypass DNS lookup).

```

and this will fail for vhosts. You should use

```auto
-H, --hostname=ADDRESS
    Host name argument for servers using host headers (virtual host)

```

---

<div class="post-metadata">

**Author:** ![eimrek](https://community.icinga.com/user_avatar/community.icinga.com/eimrek/32/6905_2.png) [@eimrek](https://community.icinga.com/u/eimrek)\
**Post date:** [July 7, 2023, 11:00am UTC](https://community.icinga.com/t/check-http-400-and-404-for-popular-websites/12288/3 "2023-07-07T11:00:10Z")

</div>

Thanks! Any idea why

```auto
$ check_http -I www.google.com 
HTTP OK: HTTP/1.0 200 OK - 19572 bytes in 0.157 second response time |time=0.156920s;;;0.000000;10.000000 size=19572B;;;0

```

works?

---

<div class="post-metadata">

**Author:** ![rsx](https://community.icinga.com/user_avatar/community.icinga.com/rsx/32/2094_2.png) [@rsx](https://community.icinga.com/u/rsx)\
**Post date:** [July 7, 2023, 11:03am UTC](https://community.icinga.com/t/check-http-400-and-404-for-popular-websites/12288/4 "2023-07-07T11:03:24Z")

</div>

I’d assume it’s not configured via vhosts.