Category: Networking

RHCSA exam taking techniques to assist in validation & debugging

If possible go graphical. This makes opening multiple terminal windows easier. But there are more than one interface available in non-graphical mode. ctrl-alt-1-9 or function keys will give you as many debugging interfaces as you need. What do you enter in your debugging interface/session? There are other logs that might be helpful but these did […]

Read More →

Mail stuck inbound ispconfig 3 galera cluster

Nail is stuck in the inbound que complaining about sql/mysql connect issues: Make sure hard coded passwords are the same in ispconfig.inc.php in /usr/local There are two config files with two password entries each they must be all the same. The password entries fo the mysql-*.cf files and there are a lt must be the […]

Read More →

Exam 2: Reality check RHCSA test question 1

No google, just documentation that can be found or installed on the system. I give myself extra time to document the process. If I cheat I don’t get credit for the answer: Question 1: Network the box: IP address=10.0.2.16/24 gateway=10.0.2.2 central server classroom.example.com is on network @ 10.0.2.10. Establish permanent network connectivity: sudo su – […]

Read More →

RHCSA SELINUX allow a apache subdirectory to be serviced

RHCSA studying. classroom.example.com 10.0.2.10 has a web server and /var/www/html/repo is where we want the yum repository to be. A little selinux problem with that in enforcing mode. yum -y install nmap  ##our test dummy. The answer: chcon -R -t httpd_sys_content_t “/var/www/html/repo/” restorecon -R /var/www/html/repo Like magic yum then works.

Read More →

The firewall project

Converting a fairly elaborate iptables based firewall with proprietary anti-spam scripts to the modern firewall-command architecture without revealing any IP. First lets take a look where we started: [root@instance-5 ~]# systemctl list-unit-files | egrep “iptables|firewall” firewalld.service masked iptables.service disabled                   This shows iptables as disabled but a […]

Read More →