Send messages to other login users through terminal

$ w
show all of the login users
$ last
show last login users

$ write username
type message
Ctr+D: end of message

unlock a deny host

1.
$ service denyhosts stop

2.
$ vim /etc/hosts.deny
delete the IP from the file

3.
$ cd /va/lib/denyhosts
$ grep -iRH IP ./*

[root@server denyhosts]# grep -iRH IP ./*

./hosts:IP:0:Sun Feb  9 11:27:57 2014

./hosts-restricted:IP:0:Sun Feb  9 11:27:57 2014

./hosts-root:IP:0:Sun Feb  9 11:27:57 2014

./hosts-valid:IP:11:Sun Feb  9 11:31:57 2014

./users-hosts:username - IP:11:Sun Feb  9 11:31:57 2014

delete the IPs from all of the files. 

4. 

$ service denyhosts start

Install svnnotify on CentOS 6

http://pkgs.org/centos-6/repoforge-i386/perl-SVN-Notify-2.80-1.el6.rf.noarch.rpm.html

Install Howto

1. Download the latest rpmforge-release rpm from

   http://apt.sw.be/redhat/el6/en/i386/rpmforge/RPMS/

2. Install rpmforge-release rpm:

   # rpm -Uvh rpmforge-release*rpm

3. Install perl-SVN-Notify rpm package:

   # yum install perl-SVN-Notify

4. You may have some error message 

Warning: post-commit hook failed (exit code 2) with output:

Use of qw(...) as parentheses is deprecated at /usr/share/perl5/vendor_perl/SVN/Notify.pm line 730.

Can't locate HTML/Entities.pm in @INC (@INC contains: /usr/local/lib64/perl5 /usr/local/share/perl5 /usr/lib64/perl5/vendor_perl /usr/share/perl5/vendor_perl /usr/lib64/perl5 /usr/share/perl5 .) at /usr/share/perl5/vendor_perl/SVN/Notify/HTML/ColorDiff.pm line 6.

                Fix it: # yum install perl-HTML-Parser