IPTables Example

Head Node IPTables example to open port 1099 and save the rules.

Add rule
iptables -A INPUT -p tcp --dport 1099 -j ACCEPT


Add rule
iptables -A OUTPUT -p tcp --dport 1099 -j ACCEPT


Save Rules in the event of reboot
/sbin/service iptables save

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Run a command on all nodes

This will run the cat command on all nodes and output the results on the head node and redirect the output to a file. This gives a list of hostnames and MAC addresses in a txt file.

[root@HOST~]#cluster-fork cat /etc/sysconfig/network-scripts/ifcfg-eth0:0 | egrep "compute|HWADDR" > HostHWaddr.txt

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