HP Cisco Nexus 5000 Cisco MDS 9000 Family CLI Configuration Guide - Release 4. - Page 358

TL Ports for Private Loops Chapter 13 Configuring Interfaces Send documentation comments to [email protected] Figure 13-4 TL Port Translation Support Examples Public target (T2) Private initiator (I4) Private target (T1) NL port NL port Private TL port loop N port F port Private initiator (I1) NL port Private loop TL port FL port F port Public initiator (I2) N port Public target (3) NL port Public loop NL port 91699 Public initiator (I3) About TL Port ALPA Caches Although TL ports cannot be automatically configured, you can manually configure entries in arbitrated loop physical address (ALPA) caches. Generally, ALPA cache entries are automatically populated when an ALPA is assigned to a device. Each device is identified by its port world wide name (pWWN). When a device is allocated an ALPA, an entry for that device is automatically created in the ALPA cache. A cache contains entries for recently allocated ALPA values. These caches are maintained on various TL ports. If a device already has an ALPA, the Cisco NX-OS software attempts to allocate the same ALPA to the device each time. The ALPA cache is maintained in persistent storage and saves information across switch reboots. The maximum cache size is 1000 entries. If the cache is full, and a new ALPA is allocated, the Cisco NX-OS software discards an inactive cache entry (if available) to make space for the new entry. See the "TL Port" section on page 13-5 for more information on TL ports. Displaying TL Port Information Private loop devices refer to legacy devices that reside on arbitrated loops. These devices are not aware of a switch fabric because they only communicate with devices on the same physical loop. The legacy devices are used in Fibre Channel networks and devices outside the loop may need to communicate with them. The communication functionality is provided through TL ports. Use the switchport mode command to configure a TL port (see the "Configuring Interface Modes" section on page 13-13). 13-32 Cisco MDS 9000 Family CLI Configuration Guide OL-18084-01, Cisco MDS NX-OS Release 4.x