Dear Alex, Thanks for your help. The command works some times though and not others, so I don't think it is the port entry (by which I take it to mean the port number you pass to check_tcp to check). Matthew <table width=100%> <tr valign=top> <td width=40%>"Heylin, Alex" <AHeylin@WeberShandwick.com> 03/12/2003 13:17 <td width=59%> <table width=100%> <tr> <td> <div align=right>To</div> <td valign=top>"'Matthew.Quinney@hollandandholland.com'" <Matthew.Quinney@hollandandholland.com>, nagios-users@lists.sourceforge.net, nagios-plugs@lists.sourceforge.net <tr> <td> <div align=right>cc</div> <td valign=top> <tr> <td> <div align=right>Subject</div> <td valign=top>RE: [Nagios-users] Nagios hosts showing as down</table> <table> <tr valign=top> <td> <td></table> </table> You might find that the "port" entry for the check_tcp check is missing, that has caused this here. As you're using check_http it should be port 80, being the HTTP port. Hope that helps point you in the right direction. Alex -----Original Message----- From: Matthew.Quinney@hollandandholland.com [mailto:Matthew.Quinney@hollandandholland.com] Sent: 03 December 2003 09:22 To: nagios-users@lists.sourceforge.net; nagios-plugs@lists.sourceforge.net Subject: [Nagios-users] Nagios hosts showing as down Dear All, I have a strange problem with Nagios V1.1 using the plugins from v1.3.1. I have a remote router which ordinarily is checked by 'check_http' every x minutes. In some cases the check fails (ADSL) so Nagios will then run the host check command 'check_tcp'. However in some cases this fails and just leaves the error message 'check_tcp: unknown argument (null). The majority of the time though this check runs just fine. My questions is therefore, what am I doing wrong ? I have been running Nagios for some time (great stuff Ethan) and this has only cropped up in the last few months. If anybody has seen this, or can help I would appreciate it greatly. Many thanks Matthew _____________________________________________________________________ This e-mail has been scanned for viruses by the uuNet Internet Managed Scanning Service - powered by MessageLabs.