HP XC System Software Administration Guide Version 3.2

12 Opening an IP Port in the Firewall
This chapter addresses the following topics:
• “Open Ports” (page 153)
• “Opening Ports in the Firewall” (page 154)
12.1 Open Ports
Each node in an HP XC system is set up with an IP firewall, for security purposes, to block
communications on unused network ports. External system access is restricted to a small set of
externally exposed ports. Table 12-1 lists the base ports that are always open by default; these
ports are labeled “External”.
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 and the network ports associated
with running services required by the HP XC system. Network interfaces attached to the external
network do not allow communications over these ports.
Table 12-1 also lists the ports open internally for the HP XC system by default.
Table 12-1 Default Open Internal and External Ports in the Firewall
UseProtocolServicePort NumberInternal or
External
Secure user logins and file transfers
tcpssh
22External
Secure Web access, used to provide system
status
tcphttps
443External
Secure user logins and file transfers
tcpssh
22Internal
Mail server
tcpsmtp
25Internal
Trivial transfer protocol
udptftp
69Internal
RPC-based code
tcp/udpsunrpc
111Internal
Network Time Protocol
tcp/udpntp
123Internal
Secure Hypertext Transfer Protocol
tcphttps
443Internal
rsync utilitytcprsync
873Internal
Required for SLURM and LSF-HPC with
SLURM
tcp/udp
various1024 to 65535Internal
The default setup restricts all other ports on the external and internal interfaces.
IMPORTANT:
For the security of your system, HP recommends that you leave these default firewall settings.
If you need to add a service that requires you to open any of the restricted ports, see “Opening
Ports in the Firewall” (page 154).
Some services require opening a service port, which requires opening an associated port in the
firewall. Determine whether you need to open a service port when installing software other than
HP XC system software.
The services running on a node can affect which additional ports are open on that node. For
example, some HP XC services like the NAT server, NIS master server, or the NFS server will
automatically open ports in the firewall on those nodes for which they are configured to run.
These services open their ports automatically. The service does not work as expected if you close
its port. Table 12-2 provides the port number or numbers for such services.
12.1 Open Ports 153