ServerBuddies Support Blog

How do I install flash plugin for Firefox in RHEL

The easiest way to download and install the flash plugins to your Red Hat Enterprise Linux system would be to run the following command.

Red Hat Enterprise Linux 5

How to set the MTU for network interface

The MTU can be set by editing the configuration file for the device. To see the devices you have use the ifconfig command:

Alternatively, you can use the ip command:

The interface eth0 has an MTU set to 1500 bytes. To change the setting temporarily (to 1200 in this example) issue the following command as root:

To make the setting permanent for eth0, edit the configuration file /etc/sysconfig/network-scripts/ifcfg-eth0 and add the line MTU=1200

Routing Table

To display the routing table in numerical addresses, one would use the “route -n” command:

With iproute, the equivalent command is “ip route show”:

Add or delete static routes from the Linux IP routing table.

You need to know the network/subnet you wish to reach, also the interface you wish this route to be added to, i.e., which interface to use to reach the subnet.

How to reach another network, 10.20.30.0/24, that is reachable via a router on the 192.168.1.0/24 network, 192.168.1.254.

The following ip route command would add the desired route to the kernel routing table:

Note: eth1 is connected to 192.168.1.0/24

Determine which network interface card (NIC)Postfix is running on?

The netstat command allows querying of IP addresses and interfaces that the Postfix daemon is listening. By default, Postfix listens on TCP port 25.

By using the netstat and grep commands for port 25, IP addresses that Postfix are listening to can be found by issuing the following command:

Example:

Here, Postfix is only listening on the IP address 127.0.0.1.

In order to list each interface’s assigned IP address, issue the following command as root: