HP XC System Software Administration Guide Version 2.1

8
OpeninganIPPortintheFirewall
This chapter includes the following topics:
• A discussion on the IP ports that are open
by default (Section 8.1)
• Information on how to open IP ports (Section 8.2)
8.1 Open Ports
Each node in an HP X C system is set up wit
h an IP firewall, for security purposes, to block
communications on unused network po
rts. External system access is restricted to a small set of
externally exposed ports.
A larger set of ports is open between members of the system but the ports are restricted to
the network interfaces that connect only members of the system as well as the network ports
associated with running services required by the H P X C system. Network interfaces that are
attached to the external network do not allow c ommunications over these ports.
Section 8.1.1 lists the base ports that are always open externally by default.
Section 8.1.2 lists the default
base ports that are always open within the internal netw orks of
the HP XC system.
The services running on a node can affect which additional ports are open on that node. For
example, services like NAT Server, NIS Server, or N FS Server may open ports in the firewall
where they are running.
To verify the actual current ports open on any node, use the iptables --list command.
Some services require open
ing a service p ort that r equires opening an associated port in the
firewall. Determine whet
her you need to open a service port when installing software other than
HP XC system software.
8.1.1 Open External Ports
Table 8-1 lists the ports
that are open for access into an HP XC system f rom the external netw ork.
Table 8-1: Open External Ports in the Firewall
Port
Service
Protocol Use
22
ssh
tcp
Secure user logins and file transfers
443
https
tcp
Secure Web access, used to provide system
status
The default setup has all other ports on the external interface restricted.
For the security of your system, it is recommended that you leave these firewall settings at their
defaults. If you need to add a service that requires you to open any of the restricted ports,
see Section 8.2.
8.1.2 Open Internal Ports
Table 8-2 lists the base set of ports that are open only to other no des of an HP XC system .
OpeninganIPPortintheFirewall 8-1