Step by step Method to install OpenNMS

Note: Make sure snmp is already installed on the Server. If not run

apt-get install snmpd -y 

Add the OpenNMS Repository to Your sources.list

deb http://debian.opennms.org stable main
deb-src http://debian.opennms.org stable main 

Add the OpenNMS PGP Key to APT

wget -O - http://debian.opennms.org/OPENNMS-GPG-KEY | sudo apt-key add - 
apt-get update 

(or)

apt-key adv --recv-keys --keyserver keyserver.ubuntu.com 4C4CBBD9
apt-get update

Installing PostgreSQL

apt-get install postgresql-8.3  

Modify pg_hba.conf file in /etc/postgresql/8.3/main/ 

comment all other lines in this file.

local   all         all                               trust
# IPv4 local connections:
host    all         all         127.0.0.1/32          trust
# IPv6 local connections:
host    all         all         ::1/128               trust
host    all         all         192.168.1.0           255.255.255.0 trust     <=== Double check 192.168.1.0 it can be 10.10.20.0

Edit postgresql.conf to Allow TCP/IP Connections

vi /etc/postgresql/8.3/main/postgresql.conf 
Uncomment following line 
listen_addresses = 'localhost' 

Restart the Postgresql Database

/etc/init.d/postgresql-8.3 restart 

Installing OpenNMS

apt-get install opennms 

we need to set opennms home in /etc/environment

add the following line
OPENNMS_HOME=/usr/share/opennms 
execute the following command for setting OPENNMS_HOME for existing session 
export OPENNMS_HOME=/usr/share/opennms 

Before you can run the post-install, OpenNMS needs to be configured to use an appropriate Java Runtime Environment (JRE). The OpenNMS tool runjava is used to set this up, and it can either search for a suitable JRE or you can tell it exactly which JRE to use.

# /usr/share/opennms/bin/runjava -s 

This tool will setup the opennms database within PostgreSQL among other things.

# /usr/share/opennms/bin/install -l /usr/local/lib -dis 

you should see similar output after executing above command

- checking table "qrtz_fired_triggers"...
- checking table "qrtz_fired_triggers"... CREATED
- granting access to 'qrtz_fired_triggers' for user 'opennms'... DONE
- checking table "qrtz_scheduler_state"...
- checking table "qrtz_scheduler_state"... CREATED
- granting access to 'qrtz_scheduler_state' for user 'opennms'... DONE
- checking table "qrtz_locks"...
- checking table "qrtz_locks"... CREATED
- granting access to 'qrtz_locks' for user 'opennms'... DONE
- creating tables... DONE
- inserting initial table data for "categories"... OK
- inserting initial table data for "qrtz_locks"... OK
- inserting initial table data for "distPoller"... OK
- checking if iplike is usable... YES
- checking for stale eventtime.so references... OK 
Installer completed successfully! 

Start opennms using the following command

/etc/init.d/opennms start 

OpenNMS will take some time to start, you can check the status of opennms using the following command

root@server1:/usr/local/lib# /etc/init.d/opennms status

OpenNMS.Eventd         : running
OpenNMS.Trapd          : running 
OpenNMS.Queued         : running
OpenNMS.Actiond        : running
OpenNMS.Capsd          : running
OpenNMS.Notifd         : running
OpenNMS.Scriptd        : running
OpenNMS.Rtcd           : running
OpenNMS.Pollerd        : running
OpenNMS.PollerBackEnd  : running
OpenNMS.Ticketer       : running
OpenNMS.Collectd       : running
OpenNMS.Threshd        : running
OpenNMS.Discovery      : running
OpenNMS.Vacuumd        : running
OpenNMS.EventTranslator: running
OpenNMS.PassiveStatusd : running
OpenNMS.Statsd         : running
OpenNMS.Importer       : running
OpenNMS.JettyServer    : running
opennms is running 

if you are able to see like above your opennms is running without any problems.
If you don't see the above output and get at error asking you to look at a log file.. /var/log/opennms/daemon/output.log and the log file mentions the following error..

An error occurred while attempting to start the "OpenNMS:Name=Dhcpd"

service (class org.opennms.netmgt.dhcpd.jmx.Dhcpd).  Shutting down and exiting.

Edit the file $OPENNMS_HOME/etc/service-configuration.xml and comment out the following portion as follows; and restart the opennms service.

<service>
               <name>OpenNMS:Name=Dhcpd</name>
               <class-name>org.opennms.netmgt.dhcpd.jmx.Dhcpd</class-name>
               <invoke at="start" pass="1" method="start"/>
               <invoke at="status" pass="0" method="status"/>
               <invoke at="stop" pass="0" method="stop"/>
</service>

Finally you can access web UI using the following URL ( replace yourhost to the IP of the opennms server)

http://yourhost:8980/opennms

Configuration of OpenNMS

Login in to the web interface  with  login / pass  admin/admin
Configure Discovery - Select  Home  /  Admin  /  Discovery  / Add New    -- Include Range.
Configure SNMP  - Select Home  / Admin  / Configure SNMP by IP

Database Login Details

opennms/postgres ( test user and password i have given )

Add Alert sound to the OpenNMS webUI 

In /usr/share/opennms/jetty-webapps/opennms/includes/servicesdown-box.jsp
Find below tags should be at the end of the file

 
  
<c:otherwise>
  <embed src="tngchime.wav" type="audio/x-pn-realaudio-plugin" hidden="true" autostart="true" loop="false" height="0"  width="0">
  <ul class="plain">
  <c:forEach var="summary" items="${summaries}">
  <c:url var="nodeLink" value="element/node.jsp">
  <c:param name="node" value="${summary.nodeId}"/>
  </c:url>
  <li><a href="${nodeLink}">${summary.nodeLabel}</a> (${summary.fuzzyTimeDown})</li>
  </c:forEach>
  </ul>
  <c:if test="${moreCount > 0}">
  <p class="noBottomMargin" align="right">
  <c:url var="moreLink" value="outage/current.jsp"/>
  <a href="${moreLink}">${moreCount} more...</a>
  </p>
  </c:if>
  </c:otherwise>

The line with the tag is new, the rest is stock
Download the following .wav file and pleace it in /usr/share/opennms/jetty-webapps/

wget http://www.nirvani.net/misc/trek_sounds/tngchime.wav

You don't need to restart OpenNMS to effect
Once you are done with above settings please install QuickTimeInstaller.exe in your windows system and restart the browser if opennms find any outages as soon as you login to OpenNMS webGUI you will hear alert sound ( check your sound volume)

Step by step method to create a SSL certificate for your websites

cd  /etc/apache2/ssl/client

Run following commands

openssl genrsa -des3 -out client.key 1024
openssl req -new -key client.key -out client.crs
openssl ca -in client.crs -cert ../ca/ca.crt -keyfile ../ca/ca.key -out client.crt
openssl pkcs12 -export -clcerts -in client.crt -inkey client.key -out client.p12



Importing Certs in Browser

Make sure to enter the password which was assigned during cert creation.

FireFox

1) Remove your current Certificates.
Firefox : Preferences > Advanced > Encryption > View Certificates > Your Certificates > Select Certificates and Delete.
2) Import : select client.p12 password: test123

Chrome

1) Remove your current Certificates.
   Chrome > Preferences > Under the Hood > Manage Certificates > Remove current one..and import the new one.
2) Import  select  Import : select client.p12 password: test123

 

How to troubleshoot IP conflicts between Servers / Systems

when we have ip conflicts between two Systems/Servers and you dont know what server ping is responding. Just give below command it requires nmap to be installed

nmap -sV -O -v ipaddress

From the below i found that the response is coming from Server1.demo.com and more to it we
can also see what operating system it is running and what are the open ports of that server.

root@naresh:/home/cp# nmap -sV -O -v 192.168.1.12

Starting Nmap 5.00 ( http://nmap.org ) at 2011-11-14 15:27 IST
NSE: Loaded 3 scripts for scanning.
Initiating ARP Ping Scan at 15:27

Scanning 192.168.1.12 [1 port]

Completed ARP Ping Scan at 15:27, 0.02s elapsed (1 total hosts)
Initiating Parallel DNS resolution of 1 host. at 15:27
Completed Parallel DNS resolution of 1 host. at 15:27, 0.03s elapsed
Initiating SYN Stealth Scan at 15:27

Scanning 192.168.1.12 [1000 ports]
Discovered open port 3306/tcp on 192.168.1.12
Discovered open port 111/tcp on 192.168.1.12
Discovered open port 80/tcp on 192.168.1.12
Discovered open port 25/tcp on 192.168.1.12
Discovered open port 8080/tcp on 192.168.1.12
Discovered open port 53/tcp on 192.168.1.12
Discovered open port 443/tcp on 192.168.1.12
Discovered open port 8009/tcp on 192.168.1.12
Discovered open port 2049/tcp on 192.168.1.12

Completed SYN Stealth Scan at 15:27, 0.04s elapsed (1000 total ports)
Initiating Service scan at 15:27

Scanning 9 services on 192.168.1.12

Completed Service scan at 15:28, 46.06s elapsed (9 services on 1 host)

Initiating OS detection (try #1) against 192.168.1.12
NSE: Script scanning 192.168.1.12.
NSE: Script Scanning completed.
Host 192.168.1.12 is up (0.000088s latency).
Interesting ports on 192.168.1.12:

Not shown: 991 closed ports
PORT     STATE SERVICE    VERSION
25/tcp   open  smtp       Postfix smtpd
53/tcp   open  tcpwrapped
80/tcp   open  http       Apache httpd 2.2.12 ((Ubuntu))
111/tcp  open  rpcbind
443/tcp  open  ssl/http   Apache httpd 2.2.12 ((Ubuntu))
2049/tcp open  rpcbind
3306/tcp open  mysql      MySQL 5.1.37-1ubuntu5.5
8009/tcp open  ajp13?
8080/tcp open  http       Apache Tomcat/Coyote JSP engine 1.1
MAC Address: 00:25:90:62:4B:62 (Super Micro Computer)
Device type: general purpose
Running: Linux 2.6.X
OS details: Linux 2.6.24 - 2.6.28
Uptime guess: 0.113 days (since Mon Nov 14 12:45:28 2011)
Network Distance: 1 hop
TCP Sequence Prediction: Difficulty=197 (Good luck!)
IP ID Sequence Generation: All zeros

Service Info: Host:  Server1.demo.com

How to get home directory of a prticular user in bash scripting or a single command

The below command gets the home directory of user if at all the user exists
 
getent passwd naresh | cut -f6 -d:

Bash script to add some line to a file at specific line number

I wrote this example to show how to append JAVA_OPTS parameters to startup.sh of tomcat



#!/bin/bash

NLINE=2
s=" export JAVA_OPTS=\"$JAVA_OPTS -Xms1024m -Xmx1024m -XX:MaxPermSize=256m\""
sp=" "
awk -vn="$NLINE" -vs="$s" -vsp="$sp" 'NR==n{$0=$0 sp s}1' startup.sh >temp
mv temp startup.sh



Sp is space given so that if something exists in that line it will give some space and
append our command or string

I just ran 'chmod -x /bin/chmod'. What did I do? How do I recover?

( or )

What to do if you cannot execute CHMOD?

This is a tricky question.. you have just removed execute permission on chmod.
Result of that is you cannot modify file permissions . Not even for chmod itself .
chmod remains usless on your system.

Here is the solution for the problem

sudo /lib/ld-linux.so.2 /bin/chmod 755 /bin/chmod

or

perl -e 'chmod(0755, "/bin/chmod")'

Solution : Backtrack 5 Live blank screen

I have downloaded backtrack 5 DVD and was trying to live boot from my Laptop.

Once i am in text mode and as root user.

I gave command startx

Just to turn command mode to GUI mode .

My system was showing a blank screen .. Searched online but did not find solutions

So I have tried my own troubleshooting methods and found that it was Graphics related issue.

Fix : Hope problem is because you are using a laptop with graphic card and BT is not able to
load specific drivers for your graphic card.
So go to BIOS either disable graphic card or

Change Graphic mode from Switching to discrete

for me it worked !! let me know if you still have problems will come up with other solutions...