Usage Note 43946: Ephemeral port range
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Ephemeral Ports
Ephemeral ports are temporary ports that are assigned by a machine's IP stack from a designated range of ports that are specifically for temporary use. When you terminate a connection to an ephemeral port, that port is available for reuse. However, most IP stacks do not reuse that port number until the entire pool of ephemeral ports have been used. So, if the client program reconnects, it is assigned a different ephemeral port number for its side of the new connection.
The following sections provide system-specific information about ephemeral ports.
IBM AIX Operating Environment
AIX uses the no command to set network options. AIX uses two separate ephemeral port ranges, one for transmission control protocol (TCP) and one for user datagram protocol (UDP). Both of these ports default to values that range from 32768 through 65535.Under AIX, you query the ephemeral port range as follows:
If you want to make this change permanent, insert your no commands in /etc/rc.tcpip. Add the commands at a location before the script starts the server daemons.
Linux Operating Environment
The Linux port range is in the ip_local_port_range file that is found in /proc/sys/net/ipv4/. To change the range, simply edit the file. Be aware that a range change that is made in this file is not permanent; the change reverts back the next time you start the system. To make the change permanent, add the following line to /etc/rc.local:
Sun Solaris Operating Environment
Solaris uses the ndd utility program to configure the IP stack. Solaris uses two separate ephemeral port ranges, one for TCP and UDP. Both ports default to values from 32768 through 65535.The following examples illustrate how you can query and change the settings:
Example 1: Query the Current Settings
Example 2: Change the Settings
These changes last until the next time you start your system.
Hewlett-Packard HP-UX Operating Environment
HP-UX also uses ndd to configure the IP stack, but it is found in the /usr/bin directory (/usr/bin/ndd). HP-UX uses two separate ephemeral port ranges, one for TCP and UDP. Both of these ports default to values from 49152 through 65535. You query and change the setting under HP-UX the same as is shown for Solaris in the previous section.As is the case with Solaris, any changes under HP-UX last only until the next time you start your system.
Microsoft Windows Operating Environment
Windows Server 2008 and later use a default range of values from 49152 through 65535. For details about how to change a range under Windows, see the Microsoft knowledge-base article 929851, "The default dynamic port range for TCP/IP has changed in Windows Vista and Windows Server 2008."Earlier releases of Windows use a default range of values from 1024 through 4999. For details about these earlier releases, see the Microsoft knowledge-base article 196271, "When you try to connect from TCP ports greater than 5000, you receive the error 'WSAENOBUFS (10055).'
Operating System and Release Information
| Product Family | Product | System | SAS Release | |
| Reported | Fixed* | |||
| SAS System | N/A | Microsoft Windows 2000 Professional | ||
| Microsoft® Windows® for 64-Bit Itanium-based Systems | ||||
| Microsoft Windows Server 2003 Datacenter 64-bit Edition | ||||
| Microsoft Windows Server 2003 Enterprise 64-bit Edition | ||||
| Microsoft Windows XP 64-bit Edition | ||||
| Microsoft® Windows® for x64 | ||||
| Microsoft Windows 2000 Advanced Server | ||||
| Microsoft Windows 2000 Datacenter Server | ||||
| Microsoft Windows 2000 Server | ||||
| Microsoft Windows Server 2003 Datacenter Edition | ||||
| Microsoft Windows Server 2003 Enterprise Edition | ||||
| Microsoft Windows Server 2003 Standard Edition | ||||
| Microsoft Windows Server 2003 for x64 | ||||
| Microsoft Windows Server 2008 | ||||
| Microsoft Windows Server 2008 for x64 | ||||
| Microsoft Windows XP Professional | ||||
| Windows 7 Enterprise 32 bit | ||||
| Windows 7 Enterprise x64 | ||||
| Windows 7 Home Premium 32 bit | ||||
| Windows 7 Home Premium x64 | ||||
| Windows 7 Professional 32 bit | ||||
| Windows 7 Professional x64 | ||||
| Windows 7 Ultimate 32 bit | ||||
| Windows 7 Ultimate x64 | ||||
| 64-bit Enabled AIX | ||||
| 64-bit Enabled HP-UX | ||||
| 64-bit Enabled Solaris | ||||
| ABI+ for Intel Architecture | ||||
| AIX | ||||
| HP-UX | ||||
| HP-UX IPF | ||||
| IRIX | ||||
| Linux | ||||
| Linux for x64 | ||||
| Linux on Itanium | ||||
| OpenVMS Alpha | ||||
| OpenVMS on HP Integrity | ||||
| Solaris | ||||
| Solaris for x64 | ||||
| Tru64 UNIX | ||||