HiperSockets™ is a System z® hardware feature that provides high performance internal communications between LPARs within the same central processor complex (CPC) without the use of any additional or external hardware equipment (for example, channel adapters, LANs, and so on).
If the host processor supports HiperSockets and Communications Server is properly configured, Communications Server will attempt to create XCF connectivity between LPARs in the same CPC using a HiperSockets link or interface. When the HiperSockets link or interface cannot be activated, TCP/IP creates a normal XCF link or interface. However, if the HiperSockets link or interface is successfully activated, but is then later stopped, TCP/IP does not create an XCF link or interface.
The HiperSockets for DYNAMICXCF device and link or interface are dynamically built and the device or interface is started during TCP/IP DYNAMICXCF stack initialization. The HiperSockets for DYNAMICXCF device and link and interface cannot be configured. The generated device name is IUTIQDIO. The generated IPv4 link name is IQDIOLNKnnnnnnnn, where nnnnnnnn is the character representation of the hexadecimal version of the DYNAMICXCF IP address. The generated IPv6 interface name is IQDIOINTF6. In general, where an XCF link or interface would normally have been used (for intra-CPC), a HiperSockets link or interface will be used.
Similar to IUTSAMEH, VTAM® will dynamically build the TRLE for IUTIQDIO when the IUTIQDIO device is started. The TRLE statement is not configured (defined) by the user.
Although HiperSockets for DYNAMICXCF is not configured with TCP/IP DEVICE and LINK or INTERFACE statements, and the TRLE is not defined by the user, the following steps must be taken to define the HiperSockets subchannel devices and IQD CHPID:
For example, if IQD CHPID 'FE'x is in use by DYNAMICXCF because of one of the following conditions, then an attempt to configure and start a user defined HiperSockets device IUTIQDFE is not allowed (IQD CHPIDs conflict):
For additional details regarding HiperSockets, see HiperSockets concepts and connectivity.