How to determine given OS in 32 bit or 64 bit in Linux

Type the following simple command in your linux boxes:

# uname-m

If it 32 bit os the output would  be  follow:

i686   ==> 32-bit kernel

If it 64 bit os the output would be follow:

x86_64 ==> 64-bit kernel

Or

 can use following command to check the OS versions:

# uname -a

# getconf LONG_BIT

# cat /proc/cpuinfo

How to fix Could not complete SSL handshake error.in rhel5

In this case, you need to check on the /etc/xinetd.d/nrpe as following.

# default: on
# description: NRPE (Nagios Remote Plugin Executor)
service nrpe
{
        flags           = REUSE
        socket_type     = stream   
 port  = 5666   
        wait            = no
        user            = nagios
 group  = nagios
        server          = /usr/local/nagios/bin/nrpe
        server_args     = -c /usr/local/nagios/etc/nrpe.cfg --inetd
        log_on_failure  += USERID
        disable               = no
 only_from                = 10.1.2.2
}

You need to make sure the only_from ip is the IP for nagios monitoring server.
If the only_from IP is not correct, rectify it and then restart xinetd.d by using the following command.
[admin@remotehost ~]$ sudo /etc/init.d/xinetd restart
Stopping xinetd:                                           [  OK  ]
Starting xinetd:                                           [  OK  ]
If the nrpe setting is already correct, then you need to check in /var/log/messages in the remote host. You might see the following error.
Jul 29 13:36:56 remotehost xinetd[7336]: FAIL: nrpe address from=10.1.2.2
Jul 29 13:36:56 remotehost xinetd[6595]: START: nrpe pid=7336 from=10.1.2.2
Jul 29 13:36:56 remotehost xinetd[6595]: EXIT: nrpe status=0 pid=7336 duration=0(sec)
Try to restart xinetd daemon using the command above and then check on /var/log/messages again. If you see the following error, it might mean that xinetd had problem to start up nrpe becuase of its bug to release the address.
Jul 29 13:35:54 remotehost xinetd[6595]: bind failed (Address already in use (errno = 98)). service = nrpe
Jul 29 13:35:54 remotehost xinetd[6595]: Service nrpe failed to start and is deactivated.
Jul 29 13:35:54 remotehost xinetd[6595]: xinetd Version 2.3.14 started with libwrap loadavg labeled-networking options compiled in.

In this case, you cannot start nrpe as embeded service in xinetd since this is a bug in xinetd. To fix this, you can start nrpe as standalone daemon. Before you started nrpe as standalone daemon, you need to verify the configuration in /usr/local/nagios/etc/nrpe.cfg. The following are two parameters that you need to take care of. The value for allowed_hosts should be the ip of nagios monitoring host and the server_port is 5666.

allowed_hosts=10.1.8.2

server_port=5666

Besides, you need to make sure xinetd is not running or you need to remove /etc/xinetd.d/nrpe and restart xinetd daemon.

Then, you can issue the following command to start nrpe as standalone daemon.

[admin@remotehost]$ /usr/local/nagios/bin/nrpe -c /usr/local/nagios/etc/nrpe.cfg -d

You should see the following log in /var/log/messages.

Jul 29 14:18:31 remotehost nrpe[5947]: Starting up daemon
Jul 29 14:18:31 remotehost nrpe[5947]: Listening for connections on port 5666
Jul 29 14:18:31 remotehost nrpe[5947]: Allowing connections from: 10.1.2.2

In this case, you can now verify the nrpe connection by running check_nrpe from nagios monitoring host as following.

[admin@monitoringhost ~]$ /usr/local/nagios/libexec/check_nrpe -H 10.1.2.12
NRPE v2.12

No more error 'CHECK_NRPE: Error - Could not complete SSL handshake.' now.

Locations of Apache conf files, binary files,Apache Module files

ServerRoot              ::      /etc/httpd
Primary Config Fle      ::      /etc/httpd/conf/httpd.conf
Other Config Files      ::      /etc/httpd/conf.d
Module Locations        ::      /usr/lib/httpd/modules
DocumentRoot            ::      /var/www/html
ErrorLog                ::      /var/log/httpd/error_log
AccessLog               ::      /var/log/httpd/access_log
cgi-bin                 ::      /var/www/cgi-bin (empty and disabled by default)
binary name and path    ::      /usr/sbin/httpd
runtime directory       ::      /etc/httpd/run

Recover MySQL root password

step1: stop mysql

root@bilal# service mysqld stop

root@bilal# /usr/sbin/mysqld --skip-grant-tables &  

step2: Login in to your mysql shell

root@bilal:/# mysql -u root

mysql> UPDATE mysql.user SET Password=PASSWORD('Newpassword') WHERE User='root';
mysql> FLUSH PRIVILEGES;