- •Contents
- •Introduction
- •1. Installation
- •3. Startup
- •4. Nagios Basics
- •6. Plugins for Network Services
- •7. Testing Local Resources
- •8. Manipulating Plugin Output
- •9. Executing Plugins via SSH
- •13. Passive Tests with the External Command File
- •15. Distributed Monitoring
- •16. The Web Interface
- •18. Monitoring Windows Servers
- •20. Monitoring SAP Systems
- •Index
Nagios
Wolfgang Barth
Nagios
System and Network Monitoring
Munich |
San Francisco |
NAGIOS. Copyright c 2006 Open Source Press GmbH
All rights reserved. No part of this work may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage or retrieval system, without the prior written permission of the copyright owner and the publisher.
Printed on recycled paper in the United States of America.
1 2 3 4 5 6 7 8 9 10 — 09 08 07 06
No Starch Press and the No Starch Press logo are registered trademarks of No Starch Press, Inc. Other product and company names mentioned herein may be the trademarks of their respective owners. Rather than use a trademark symbol with every occurrence of a trademarked name, we are using the names only in an editorial fashion and to the benefit of the trademark owner, with no intention of infringement of the trademark.
Publisher: William Pollock Cover Design: Octopod Studios
U.S. edition published by No Starch Press, Inc.
555 De Haro Street, Suite 250, San Francisco, CA 94107
phone: 415.863.9900; fax: 415.863.9950; info@nostarch.com; http://www.nostarch.com
Original edition c 2005 Open Source Press GmbH Published by Open Source Press GmbH, Munich, Germany Publisher: Dr. Markus Wirtz
Original ISBN 3-937514-09-0
For information on translations, please contact
Open Source Press GmbH, Amalienstr. 45 Rg, 80799 Munchen,¨ Germany
phone +49.89.28755562; fax +49.89.28755563; info@opensourcepress.de; http://www.opensourcepress.de
The information in this book is distributed on an “As Is” basis, without warranty. While every precaution has been taken in the preparation of this work, neither the author nor Open Source Press GmbH nor No Starch Press, Inc. shall have any liability to any person or entity with respect to any loss or damage caused or alleged to be caused directly or indirectly by the information contained in it.
Library of Congress Cataloging-in-Publication Data
Barth, Wolfgang
Nagios : system and network monitoring / Wolfgang Barth.-- 1st ed. p. cm.
Includes index. ISBN 1-59327-070-4
1. Computer networks--Management--Automation. I. Title. TK5105.5.B374 2005 004.6--dc22
2005026745
Contents
Introduction |
15 |
From Source Code to a Running Installation |
23 |
1 Installation |
25 |
1.1Compiling the Source Code . . . . . . . . . . . . . . . . . . . . . . 26
1.2Installing and Testing Plugins . . . . . . . . . . . . . . . . . . . . . 30
|
1.2.1 |
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . |
30 |
|
1.2.2 |
Plugin test . . . . . . . . . . . . . . . . . . . . . . . . . . |
32 |
1.3 |
Configuration of the Web Interface . . . . . . . . . . . . . . . . . |
33 |
|
|
1.3.1 Setting Up Apache . . . . . . . . . . . . . . . . . . . . . . |
33 |
|
|
1.3.2 |
User Authentication . . . . . . . . . . . . . . . . . . . . . |
34 |
2 Nagios Configuration |
37 |
||
2.1 |
The Main Configuration File nagios.cfg . . . . . . . . . . . . . . . |
38 |
|
2.2 |
Objects—an Overview . . . . . . . . . . . . . . . . . . . . . . . . . |
41 |
2.3Defining the Machines to Be Monitored, with host . . . . . . . . . 44
2.4Grouping Computers Together with hostgroup . . . . . . . . . . . 46
2.5Defining Services to Be Monitored with service . . . . . . . . . . . 47
2.6 Grouping Services Together with servicegroup . . . . . . . . . . . 50
2.7Defining Addressees for Error Messages: contact . . . . . . . . . . 50
2.8The Message Recipient: contactgroup . . . . . . . . . . . . . . . . 52
2.9 |
When Nagios Needs to Do Something: the command Object . . . |
53 |
2.10 |
Defining a Time Period with timeperiod . . . . . . . . . . . . . . . |
54 |
5
Contents
2.11 Templates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
2.12Configuration Aids for Those Too Lazy to Type . . . . . . . . . . . . 56
2.12.1Defining services for several computers . . . . . . . . . . . 56
2.12.2One host group for all computers . . . . . . . . . . . . . . 57
2.12.3Other configuration aids . . . . . . . . . . . . . . . . . . . 57
2.13CGI Configuration in cgi.cfg . . . . . . . . . . . . . . . . . . . . . 57
2.14The Resources File resource.cfg . . . . . . . . . . . . . . . . . . . . 59
3 Startup |
61 |
3.1Checking the Configuration . . . . . . . . . . . . . . . . . . . . . . 61
3.2Getting Monitoring Started . . . . . . . . . . . . . . . . . . . . . . 63
3.2.1 Manual start . . . . . . . . . . . . . . . . . . . . . . . . . 63
3.2.2Automatic start . . . . . . . . . . . . . . . . . . . . . . . . 64
3.2.3Making configuration changes come into effect . . . . . . 64
3.3 Overview of the Web Interface . . . . . . . . . . . . . . . . . . . . 64
In More Detail . . . |
69 |
4 Nagios Basics |
71 |
4.1 Taking into Account the Network Topology . . . . . . . . . . . . . |
72 |
4.2Forced Host Checks vs. Periodic Reachability Tests . . . . . . . . . . 75
4.3 States of Hosts and Services . . . . . . . . . . . . . . . . . . . . . |
75 |
5 Service Checks and How They Are Performed |
79 |
5.1Testing Network Services Directly . . . . . . . . . . . . . . . . . . . 81
5.2 |
Running Plugins via Secure Shell on the Remote Computer . . . . |
82 |
5.3 |
The Nagios Remote Plugin Executor . . . . . . . . . . . . . . . . . |
82 |
5.4 |
Monitoring via SNMP . . . . . . . . . . . . . . . . . . . . . . . . . |
83 |
5.5The Nagios Service Check Acceptor . . . . . . . . . . . . . . . . . . 84
6 Plugins for Network Services |
85 |
6.1 Standard Options . . . . . . . . . . . . . . . . . . . . . . . . . . . |
87 |
6.2Reachability Test with Ping . . . . . . . . . . . . . . . . . . . . . . 88
6.2.1 check_icmp as a service check . . . . . . . . . . . . . . . 90
6
Contents
6.2.2check_icmp as a host check . . . . . . . . . . . . . . . . . 91
6.3Monitoring Mail Servers . . . . . . . . . . . . . . . . . . . . . . . . 92
6.3.1Monitoring SMTP with check_smtp . . . . . . . . . . . . . 92
6.3.2 POP and IMAP . . . . . . . . . . . . . . . . . . . . . . . . 95
6.4Monitoring FTP and Web Servers . . . . . . . . . . . . . . . . . . . 97
6.4.1FTP services . . . . . . . . . . . . . . . . . . . . . . . . . . 97
6.4.2Web server control via HTTP . . . . . . . . . . . . . . . . . 98
6.4.3Monitoring Web proxies . . . . . . . . . . . . . . . . . . . 101
6.5 Domain Name Server under Control . . . . . . . . . . . . . . . . . 105
6.5.1DNS check with nslookup . . . . . . . . . . . . . . . . . . 106
6.5.2Monitoring the name server with dig . . . . . . . . . . . . 107
6.6Querying the Secure Shell Server . . . . . . . . . . . . . . . . . . . 108
6.7 Generic Network Plugins . . . . . . . . . . . . . . . . . . . . . . . 110
6.7.1Testing TCP ports . . . . . . . . . . . . . . . . . . . . . . . 110
6.7.2 Monitoring UDP ports . . . . . . . . . . . . . . . . . . . . 112
6.8Monitoring Databases . . . . . . . . . . . . . . . . . . . . . . . . . 114
|
6.8.1 |
PostgreSQL . . . . . . . . . . . . . . . . . . . . . . . . . . |
115 |
|
6.8.2 |
MySQL . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
119 |
6.9 |
Monitoring LDAP Directory Services . . . . . . . . . . . . . . . . . |
121 |
|
6.10 |
Checking a DHCP Server . . . . . . . . . . . . . . . . . . . . . . . . |
124 |
|
6.11 |
Monitoring UPS with the Network UPS Tools . . . . . . . . . . . . |
126 |
|
7 Testing Local Resources |
133 |
||
7.1 |
Free Hard Drive Capacity . . . . . . . . . . . . . . . . . . . . . . . |
134 |
7.2Utilization of the Swap Space . . . . . . . . . . . . . . . . . . . . . 136
7.3Testing the System Load . . . . . . . . . . . . . . . . . . . . . . . . 137
7.4 Monitoring Processes . . . . . . . . . . . . . . . . . . . . . . . . . 138
7.5Checking Log Files . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
|
7.5.1 |
The standard plugin check_log . . . . . . . . . . . . . . . |
142 |
|
7.5.2 |
The modern variation: check_logs.pl . . . . . . . . . . . . |
143 |
7.6 |
Keeping Tabs on the Number of Logged-in Users . . . . . . . . . . |
144 |
|
7.7 |
Checking the System Time . . . . . . . . . . . . . . . . . . . . . . |
145 |
|
|
7.7.1 |
Checking the system time via NTP . . . . . . . . . . . . . . |
145 |
7
Contents
7.7.2 |
Checking system time with the time protocol . . . . . . . 146 |
7.8Regularly Checking the Status of the Mail Queue . . . . . . . . . . 147
7.9 Keeping an Eye on the Modification Date of a File . . . . . . . . . 148
7.10Monitoring UPSs with apcupsd . . . . . . . . . . . . . . . . . . . . 149
7.11Nagios Monitors Itself . . . . . . . . . . . . . . . . . . . . . . . . . 150
7.11.1Running the plugin manually with a script . . . . . . . . . 151
7.11.2check_nagios as a tool for CGI programs . . . . . . . . . . 152
7.12 |
Hardware Checks with LM Sensors . . . . . . . . . . . . . . . . . . |
152 |
7.13 |
The Dummy Plugin for Tests . . . . . . . . . . . . . . . . . . . . . |
154 |
8 Manipulating Plugin Output |
155 |
8.1Negating Plugin Results . . . . . . . . . . . . . . . . . . . . . . . . 155
8.2Inserting Hyperlinks with urlize . . . . . . . . . . . . . . . . . . . 156
9 Executing Plugins via SSH |
157 |
9.1The check_by_ssh Plugin . . . . . . . . . . . . . . . . . . . . . . . 158
9.2Configuring SSH . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160 9.2.1 Generating SSH key pairs on the Nagios server . . . . . . . 160
9.2.2 |
Setting up the user nagios on the target host . . . . . . . |
161 |
9.2.3 |
Checking the SSH connection and check_by_ssh . . . . . |
161 |
9.3 Nagios Configuration . . . . . . . . . . . . . . . . . . . . . . . . . |
162 |
|
10 The Nagios Remote Plugin Executor (NRPE) |
165 |
10.1Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166
10.1.1Distribution-specific packages . . . . . . . . . . . . . . . . 166
10.1.2Installation from the source code . . . . . . . . . . . . . . 167
10.2Starting via the inet Daemon . . . . . . . . . . . . . . . . . . . . . 168
10.2.1xinetd configuration . . . . . . . . . . . . . . . . . . . . . 168
|
10.2.2 |
inetd configuration . . . . . . . . . . . . . . . . . . . . . |
169 |
10.3 |
NRPE Configuration on the Computer to Be Monitored . . . . . . . |
170 |
|
|
10.3.1 |
Passing parameters on to local plugins . . . . . . . . . . . |
171 |
10.4 |
Nagios Configuration . . . . . . . . . . . . . . . . . . . . . . . . . |
172 |
|
|
10.4.1 |
NRPE without passing parameters on . . . . . . . . . . . . |
172 |
|
10.4.2 |
Passing parameters on in NRPE . . . . . . . . . . . . . . . |
173 |
8
Contents
10.4.3 Optimizing the configuration . . . . . . . . . . . . . . . . |
173 |
10.5 Indirect Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
174 |
11 Collecting Information Relevant for Monitoring with SNMP |
177 |
11.1Introduction to SNMP . . . . . . . . . . . . . . . . . . . . . . . . . 178 11.1.1 The Management Information Base . . . . . . . . . . . . . 179
|
11.1.2 |
SNMP protocol versions . . . . . . . . . . . . . . . . . . . |
183 |
11.2 |
NET-SNMP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
184 |
|
|
11.2.1 Tools for SNMP requests . . . . . . . . . . . . . . . . . . . |
184 |
|
|
11.2.2 |
The NET-SNMP daemon . . . . . . . . . . . . . . . . . . . |
187 |
11.3 |
Nagios’s Own SNMP Plugins . . . . . . . . . . . . . . . . . . . . . |
196 |
11.3.1The generic SNMP plugin check_snmp . . . . . . . . . . . 196
11.3.2Checking several interfaces simultaneously . . . . . . . . . 201
11.3.3Testing the operating status of individual interfaces . . . . 203
11.4Other SNMP-based Plugins . . . . . . . . . . . . . . . . . . . . . . 205
11.4.1Monitoring hard drive space and processes with nagios- snmp-plugins . . . . . . . . . . . . . . . . . . . . . . . . 205
11.4.2Observing the load on network interfaces with checkiftraffic . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207
11.4.3The manubulon.com plugins for special application pur-
poses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
209 |
12 The Nagios Notification System |
215 |
12.1Who Should be Informed of What, When? . . . . . . . . . . . . . . 216
12.2When Does a Message Occur? . . . . . . . . . . . . . . . . . . . . 217
12.3The Message Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . 217
12.3.1 |
Switching messages on and off systemwide . . . . . . . . |
218 |
12.3.2 Enabling and suppressing computer and service-related |
|
|
|
messages . . . . . . . . . . . . . . . . . . . . . . . . . . . |
219 |
12.3.3 Person-related filter options . . . . . . . . . . . . . . . . . |
221 |
|
12.3.4 |
Case examples . . . . . . . . . . . . . . . . . . . . . . . . |
222 |
12.4External Notification Programs . . . . . . . . . . . . . . . . . . . . 224
12.4.1Notification via e-mail . . . . . . . . . . . . . . . . . . . . 225
12.4.2Notification via SMS . . . . . . . . . . . . . . . . . . . . . 227
9
Contents
12.5Escalation Management . . . . . . . . . . . . . . . . . . . . . . . . 231
12.6Dependences between Hosts and Services as a Filter Criterion . . . 234 12.6.1 The standard case: service dependencies . . . . . . . . . . 234
12.6.2 Only in exceptional cases: host dependencies . . . . . . . |
238 |
13 Passive Tests with the External Command File |
239 |
13.1 The Interface for External Commands . . . . . . . . . . . . . . . . |
240 |
13.2Passive Service Checks . . . . . . . . . . . . . . . . . . . . . . . . . 241
13.3Passive Host Checks . . . . . . . . . . . . . . . . . . . . . . . . . . 242
13.4 |
Reacting to Out-of-Date Information of Passive Checks . . . . . . |
243 |
14 The Nagios Service Check Acceptor (NSCA) |
247 |
|
14.1 |
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
248 |
14.2 |
Configuring the Nagios Server . . . . . . . . . . . . . . . . . . . . |
249 |
14.2.1The configuration file nsca.cfg . . . . . . . . . . . . . . . 249
14.2.2Configurung the inet daemon . . . . . . . . . . . . . . . . 251
14.3Client-side Configuration . . . . . . . . . . . . . . . . . . . . . . . 252
14.4 Sending Test Results to the Server . . . . . . . . . . . . . . . . . . 253
14.5Application Example I: Integrating syslog and Nagios . . . . . . . . 254 14.5.1 Preparing syslog-ng for use with Nagios . . . . . . . . . . 255
14.5.2 Nagios configuration: volatile services . . . . . . . . . . . 257
14.5.3Resetting error states manually . . . . . . . . . . . . . . . 258
14.6Application Example II: Processing SNMP Traps . . . . . . . . . . . 260
14.6.1 |
Receiving traps with snmptrapd . . . . . . . . . . . . . . |
260 |
14.6.2 |
Passing on traps to NSCA . . . . . . . . . . . . . . . . . . |
261 |
14.6.3 |
The matching service definition . . . . . . . . . . . . . . . |
263 |
15 Distributed Monitoring |
265 |
15.1Switching On the OCSP/OCHP Mechanism . . . . . . . . . . . . . . 266
15.2Defining OCSP/OCHP Commands . . . . . . . . . . . . . . . . . . . 267
15.3Practical Scenarios . . . . . . . . . . . . . . . . . . . . . . . . . . . 269
10
Contents
15.3.1Avoiding redundancy in configuration files . . . . . . . . . 269
15.3.2Defining templates . . . . . . . . . . . . . . . . . . . . . . 270
16 The Web Interface |
273 |
||
16.1 |
Recognizing and Acting On Problems . . . . . . . . . . . . . . . . |
275 |
|
|
16.1.1 |
Comments on problematic hosts . . . . . . . . . . . . . . |
276 |
|
16.1.2 |
Taking responsibility for problems: acknowledgements . . |
278 |
16.2 |
An Overview of the Individual CGI Programs . . . . . . . . . . . . . |
279 |
|
|
16.2.1 |
Variations in status display: status.cgi . . . . . . . . . . . |
279 |
16.2.2Additional information and control center: extinfo.cgi . . 284
16.2.3Interface for external commands: cmd.cgi . . . . . . . . . 288
16.2.4 The most important things at a glance: tac.cgi . . . . . . 290
16.2.5Network plan: the topological map of the network (statusmap.cgi) . . . . . . . . . . . . . . . . . . . . . . . . . . 291
16.2.6Navigation in 3D: statuswrl.cgi . . . . . . . . . . . . . . . 293
16.2.7Querying the status with a cell phone: statuswml.cgi . . . 295
16.2.8Analyzing disrupted partial networks: outages.cgi . . . . . 295
16.2.9Querying the object definition with config.cgi . . . . . . . 295
16.2.10 Availability statistics: avail.cgi . . . . . . . . . . . . . . . 296
16.2.11What events occur, how often? histogram.cgi . . . . . . . 298
16.2.12Filtering log entries after specific states: history.cgi . . . . 299
16.2.13 |
Who was told what, when? notifications.cgi . . . . . . . |
300 |
16.2.14 |
Showing all logfile entries: showlog.cgi . . . . . . . . . . |
301 |
16.2.15 |
Evaluating whatever you want: summary.cgi . . . . . . . |
301 |
16.2.16 |
Following states graphically over time: trends.cgi . . . . . |
303 |
16.3 Planning Downtimes . . . . . . . . . . . . . . . . . . . . . . . . . |
304 |
|
16.3.1 |
Maintenance periods for hosts . . . . . . . . . . . . . . . |
305 |
16.3.2 Downtime for services . . . . . . . . . . . . . . . . . . . . 306
16.4Additional Information on Hosts and Services . . . . . . . . . . . . 307
16.4.1 |
Extended host information . . . . . . . . . |
. . . . . . . . |
307 |
16.4.2 |
Extended service information . . . . . . . . |
. . . . . . . . |
310 |
16.5 Configuration Changes through the Web Interfaces: |
the Restart |
|
|
Problem . . . . . . . . . . . . . . . . . . . . . . . . |
. . . . . . . . |
311 |
11
Contents
17 Graphic Display of Performance Data |
313 |
17.1 Processing Plugin Performance Data with Nagios . . . . . . . . . . |
314 |
17.1.1 The template mechanism . . . . . . . . . . . . . . . . . . |
314 |
17.1.2Using external commands to process performance data . . 317
17.2Graphs for the Web with Nagiosgraph . . . . . . . . . . . . . . . . 317
17.2.1Basic installation . . . . . . . . . . . . . . . . . . . . . . . 318
17.2.2Configuration . . . . . . . . . . . . . . . . . . . . . . . . . 319
17.3 Preparing Performance Data for Evaluation with Perf2rrd . . . . . |
325 |
17.3.1 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . |
326 |
17.3.2Nagios configuration . . . . . . . . . . . . . . . . . . . . . 326
17.3.3Perf2rrd in practice . . . . . . . . . . . . . . . . . . . . . . 327
17.4The Graphics Specialist drraw . . . . . . . . . . . . . . . . . . . . . 330
17.4.1 |
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . |
330 |
17.4.2 Configuration . . . . . . . . . . . . . . . . . . . . . . . . . |
331 |
|
17.4.3 |
Practical application . . . . . . . . . . . . . . . . . . . . . |
332 |
17.5 Automated to a Large Extent: NagiosGrapher . . . . . . . . . . . . |
336 |
|
17.5.1 |
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . |
336 |
17.5.2 Configuration . . . . . . . . . . . . . . . . . . . . . . . . . 338
17.6Other tools and the limits of graphic evaluation . . . . . . . . . . . 349
Special Applications |
351 |
||
18 Monitoring Windows Servers |
353 |
||
18.1 NSClient and NC |
|
Net . . . . . . . . . . . . . . . . . . . . . . . . . |
354 |
18.1.1 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . |
354 |
18.1.2The check_nt plugin . . . . . . . . . . . . . . . . . . . . . 355
18.1.3Commands which can be run with NSClient and NC Net . 356
18.1.4 |
Advanced functions of NC |
|
Net . . . . . . . . . . . . . . . |
363 |
||
18.2 NRPE for Windows: NRPE |
|
NT . . . . . . . . . . . . . . . . . . . . . |
371 |
|||
18.2.1 Installation and configuration . . . . . . . . . . . . . . . . |
372 |
|||||
18.2.2 |
Function test . . . . . . . . . . . . . . . . . . . . . . . . . |
373 |
18.2.3The Cygwin plugins . . . . . . . . . . . . . . . . . . . . . . 373
18.2.4Perl plugins in Windows . . . . . . . . . . . . . . . . . . . 374
12
Contents
19 Monitoring Room Temperature and Humidity |
377 |
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19.1 |
Sensors and Software . . . . . . . . . . . . . . . . . . . . . . . . . |
378 |
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19.1.1 |
The PCMeasure software for Linux . . . . . . . . . . . . . |
378 |
|
19.1.2 |
The query protocol . . . . . . . . . . . . . . . . . . . . . . |
379 |
19.2 |
The Nagios Plugin check_pcmeasure . . . . . . . . . . . . . . . . |
379 |
20 Monitoring SAP Systems |
383 |
20.1 Checking without a Login: sapinfo . . . . . . . . . . . . . . . . . . |
384 |
20.1.1 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . |
384 |
20.1.2First test . . . . . . . . . . . . . . . . . . . . . . . . . . . . 384
20.1.3The plugin check_sap.sh . . . . . . . . . . . . . . . . . . . 386
20.2 Monitoring with SAP’s Own Monitoring System (CCMS) . . . . . . 388
20.2.1CCMS—a short overview . . . . . . . . . . . . . . . . . . . 388
20.2.2Obtaining the necessary SAP usage permissions for Nagios 390
20.2.3Monitors and templates . . . . . . . . . . . . . . . . . . . 392
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20.2.4 |
The CCMS plugins . . . . . . . . . . . . . . . . . . . . . . |
394 |
|
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20.2.5 |
Performance optimization . . . . . . . . . . . . . . . . . . |
398 |
Appendixes |
|
399 |
||
A |
Rapidly Alternating States: Flapping |
401 |
||
|
A.1 |
Flap Detection with Services . . . . . . . . . . . . . . . . . . . . . |
402 |
|
|
|
A.1.1 |
Nagios configuration . . . . . . . . . . . . . . . . . . . . . |
403 |
|
|
A.1.2 |
The history memory and the chronological progression of |
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|
|
|
the changes in state . . . . . . . . . . . . . . . . . . . . . |
404 |
|
|
A.1.3 |
Representation in the Web interface . . . . . . . . . . . . |
404 |
|
A.2 |
Flap Detection for Hosts . . . . . . . . . . . . . . . . . . . . . . . . |
406 |
|
B |
Event Handlers |
409 |
||
|
B.1 |
Execution Times for the Event Handler . . . . . . . . . . . . . . . . |
410 |
|
|
B.2 |
Defining the Event Handler in the Service Definition . . . . . . . . |
411 |
|
|
B.3 |
The Handler Script . . . . . . . . . . . . . . . . . . . . . . . . . . . |
411 |
|
|
B.4 |
Things to Note When Using Event Handlers . . . . . . . . . . . . . |
413 |
13
Contents
C Writing Your Own Plugins: Monitoring Oracle with the |
|
||
Instant Client |
415 |
||
C.1 |
Installing the Oracle Instant Client . . . . . . . . . . . . . . . . . . |
416 |
|
C.2 |
Establishing a Connection to the Oracle Database . . . . . . . . . . |
417 |
|
C.3 |
A Wrapper Plugin for sqlplus . . . . . . . . . . . . . . . . . . . . . |
417 |
|
|
C.3.1 |
How the wrapper works . . . . . . . . . . . . . . . . . . . |
418 |
|
C.3.2 |
The Perl plugin in detail . . . . . . . . . . . . . . . . . . . |
419 |
D An Overview of the Nagios Configuration Parameters |
423 |
||
D.1 |
The Main Configuration File nagios.cfg . . . . . . . . . . . . . . . |
424 |
|
D.2 |
CGI Configuration in cgi.cfg . . . . . . . . . . . . . . . . . . . . . |
443 |
|
|
D.2.1 |
Authentication parameters . . . . . . . . . . . . . . . . . |
443 |
|
D.2.2 |
Other Parameters . . . . . . . . . . . . . . . . . . . . . . . |
444 |
Index |
|
|
447 |
14