<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> <META content="MSHTML 6.00.2800.1106" name=GENERATOR> <STYLE>@page Section1 {size: 8.5in 11.0in; margin: 1.0in 1.25in 1.0in 1.25in; } P.MsoNormal { FONT-SIZE: 12pt; MARGIN: 0in 0in 0pt; FONT-FAMILY: "Times New Roman" } LI.MsoNormal { FONT-SIZE: 12pt; MARGIN: 0in 0in 0pt; FONT-FAMILY: "Times New Roman" } DIV.MsoNormal { FONT-SIZE: 12pt; MARGIN: 0in 0in 0pt; FONT-FAMILY: "Times New Roman" } A:link { COLOR: blue; TEXT-DECORATION: underline } SPAN.MsoHyperlink { COLOR: blue; TEXT-DECORATION: underline } A:visited { COLOR: purple; TEXT-DECORATION: underline } SPAN.MsoHyperlinkFollowed { COLOR: purple; TEXT-DECORATION: underline } P { FONT-SIZE: 12pt; MARGIN-LEFT: 0in; MARGIN-RIGHT: 0in; FONT-FAMILY: "Times New Roman" } SPAN.EmailStyle17 { COLOR: windowtext; FONT-FAMILY: Arial } DIV.Section1 { page: Section1 } </STYLE> </HEAD> <BODY lang=EN-US vLink=purple link=blue> <DIV>Dale:</DIV> <DIV>I believe what you are looking for is a parent-child relationship, rather than a host-dependency.</DIV> <DIV> </DIV> <DIV>Given the following network (forgive the ASCII art ;-) ):</DIV> <DIV> Nagios | Firewall | *-------*-------* | | | A B C </DIV> <DIV>I would set this up as:</DIV> <DIV> define host{ host_name A parent Firewall }</DIV> <DIV> </DIV> <DIV> define host{ host_name B parent Firewall }</DIV> <DIV> </DIV> <DIV> define host{ host_name C parent Firewall }</DIV> <DIV> define host{ host_name Firewall } </DIV> <DIV>You will note that there is no parent defined for 'Firewall'. This is because 'Firewall' is local to Nagios (meaning, no the same network/subnet).</DIV> <DIV> </DIV> <DIV>In this case, if any of 'A','B', or 'C' goes down, Nagios will check 'Firewall'. If 'Firewall' is down, Nagios will tell you about it, but NOT about 'A', 'B', or 'C' ('Firewall's children). This will show up in the web interface as a 'network outage', instead of a simple 'host' outage.</DIV> <DIV> </DIV> <DIV>I do not use host dependencies personally, so I could not comment as to a scenario in which they would be useful.</DIV> <DIV> </DIV> <DIV>Important note however, if you want 'Firewall' to be checked ONLY when any of it's children are down, do not define any services for this host. If, however, you want Nagios to "active" check this device, setup a simple 'check_ping' service for it. I have not completely tested this out, but I do believe that having an "active" check on firewall in this configuration will allow Nagios to pick up a failure on that device quicker (this may not be the case thought).</DIV> <DIV> </DIV> <DIV>I hope that helps.</DIV> <DIV> </DIV> <DIV>-Darren</DIV> <DIV> </DIV> <DIV>-----Original Message----- From: nagios-users-admin@lists.sourceforge.net [mailto:nagios-users-admin@lists.sourceforge.net]On Behalf Of Dale Hobbs Sent: Thursday, August 19, 2004 11:14 AM To: nagios-users@lists.sourceforge.net Subject: [Nagios-users] Question regarding Dependencies </DIV> <BLOCKQUOTE dir=ltr style="MARGIN-RIGHT: 0px"> <DIV class=Section1> For give me if this question has been asked before. I have read the docs in regards to dependencies but am still a bit unclear as to the internal workings. If I have 3 servers (www1, www2, www3) on the outside of my firewall with the following dependencies set up for each of the 3 servers: define hostdependency{ host_name www1 dependent_host_name firewall notification_failure_criteria d,u } If my firewall goes down, obviously it will notify me that the firewall is down but will it also notify me that it can’t contact each of the 3 servers as well? Also if one of the servers goes down is Nagios smart enough to check the firewall first to make sure that it is still available before notifying me that the server is down in case that it can’t contact the server because the firewall is down? Dale Hobbs End User Support Chancery Software -- The Right Partner. The Right Solution. Tel: 604-294-1233 Ext.4744 Fax: 604-294-2225 Email: dhobbs@chancery.com <A href="http://www.chancery.com/" target=_blank>http://www.chancery.com</A> This electronic email transmission contains confidential information intended only for the named person(s). Any use, distribution, copying or disclosure by any other person is strictly prohibited. If you received this transmission in error, please notify the sender immediately so that we may correct our internal records. Please then delete the original message. Thank You. </DIV></BLOCKQUOTE></BODY></HTML> <PRE>****************************************************************************************** The information contained in this message, including attachments, may contain privileged or confidential information that is intended to be delivered only to the person identified above. If you are not the intended recipient, or the person responsible for delivering this message to the intended recipient, ALLTEL requests that you immediately notify the sender and asks that you do not read the message or its attachments, and that you delete them without copying or sending them to anyone else. </PRE>