The standard iptables tools are installed, and all you would have to do, is enter your desired rules in
/etc/sysconfig/iptables, followed by
service iptables restart AND a final one-off run of
chkconfig iptables on. The
service call enables your firewall rules, while the
chkconfig call enables activation of the firewall rules on boot. Until and unless the
chkconfig step is taken, your firewall rules won't persist when the VM is rebooted. Besides this, somewhat low-level, method of configuring an iptables firewall there are also various user-friendly frontends available for installation with
Troubleshooting Network Problems
The most common problem is with how CentOS 6 handles interface discovery, it wants to hang onto MAC addresses which of course in a virtual environment you want managed by the Hypervisor.
Run the command "ifconfig -a", the result should look like this:
[root@nmis64 ~]# ifconfig -a eth0 Link encap:Ethernet HWaddr 00:0C:29:E8:CF:F9 inet addr:192.168.1.42 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: 2001:470:1f05:5a0:20c:29ff:fee8:cff9/64 Scope:Global inet6 addr: fe80::20c:29ff:fee8:cff9/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:6640287 errors:0 dropped:0 overruns:0 frame:0 TX packets:4282058 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:974072080 (928.9 MiB) TX bytes:606513312 (578.4 MiB) lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:2337305 errors:0 dropped:0 overruns:0 frame:0 TX packets:2337305 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:371309377 (354.1 MiB) TX bytes:371309377 (354.1 MiB)
If you do not see an interface called eth0 then run this command and reboot your VM.
rm -f /etc/udev/rules.d/70-persistent-net.rules reboot
Accessing the Application Modules on the VM
NOTE - If you do not know the IP address of your install run the command ifconfig and use the IP address next to inet addr. Running the command hostname will give you the host name of the VM.
You will be presented with a menu of the installed tools, similar to the following screenshot:
Adding to /omk to the end of the URL ie http://192.168.1.42/omk will take you to a page similar to the one below:following screen.
All the module names are clickable and link to the respective applications; but you can also navigate directly to NMIS, Open-AudIT or any of the other Opmantek applications.