Predefined NAT benefits or limitations
A.
B.
C.
D.
Correct Answer:
Explanation/Reference:
http://www.cisco.com/c/en/us/td/docs/routers/crs/software/crs_r4-3/cg_nat/configuration/guide/cgnat_cg43crs/cgc43cgn.html#pgfId-1078599
The considerations and the limitations of the predefined mode for NAT 44 are as follows:
+ You can configure the predefined mode for each of the inside VRF instance.
+ A new parameter, private address range, has been added to the NAT 44 configuration for the predefined mode. You can specify a minimum of one private address range to a maximum of eight private address ranges. Ensure that you specify atleast one private address range because the available public addresses and the associated ports are mapped to the private addreses specified in this range. If the incoming packet has an address that is outside the private address range, then the packet is discarded. Ensure that the sum of all addresses should not exceed one million across all predefined mode-enabled VRFs.
+ The Bulk Port Allocation configuration is not available in the predefined mode. If you try to configure Bulk Port Allocation on an inside VRF that has the predefined mode enabled, the configuration is rejected during verification.
+ The port-preservation option is not available in the predefined mode.
+ The global port limit parameter is not available for the predefined mode. Even though you will be allowed to configure the global port limit, the inside VRF, which has predefined mode enabled, ignores that port limit and uses the port limit configured by the algorithm.
+ If you turn the predefined mode on or off for an inside VRF during the active translations, all the translations on that VRF are deleted.
+ If a request for configuring static port on a private address that is not in the address range is made, the request is rejected.
+ Ensure that you configure NetFlow or syslog only if it is very much required.
+ Any configuration change that results in changes in mapping deletes the existing translations. Therefore, ensure that you record such configuration changes. You might need this information to trace the port usage by a subscriber.
+ Ensure uniform port allocation uniform for all subscribers
Explanation/Reference:
http://www.cisco.com/c/en/us/td/docs/routers/crs/software/crs_r4-3/cg_nat/configuration/guide/cgnat_cg43crs/cgc43cgn.html#pgfId-1078599
The considerations and the limitations of the predefined mode for NAT 44 are as follows:
+ You can configure the predefined mode for each of the inside VRF instance.
+ A new parameter, private address range, has been added to the NAT 44 configuration for the predefined mode. You can specify a minimum of one private address range to a maximum of eight private address ranges. Ensure that you specify atleast one private address range because the available public addresses and the associated ports are mapped to the private addreses specified in this range. If the incoming packet has an address that is outside the private address range, then the packet is discarded. Ensure that the sum of all addresses should not exceed one million across all predefined mode-enabled VRFs.
+ The Bulk Port Allocation configuration is not available in the predefined mode. If you try to configure Bulk Port Allocation on an inside VRF that has the predefined mode enabled, the configuration is rejected during verification.
+ The port-preservation option is not available in the predefined mode.
+ The global port limit parameter is not available for the predefined mode. Even though you will be allowed to configure the global port limit, the inside VRF, which has predefined mode enabled, ignores that port limit and uses the port limit configured by the algorithm.
+ If you turn the predefined mode on or off for an inside VRF during the active translations, all the translations on that VRF are deleted.
+ If a request for configuring static port on a private address that is not in the address range is made, the request is rejected.
+ Ensure that you configure NetFlow or syslog only if it is very much required.
+ Any configuration change that results in changes in mapping deletes the existing translations. Therefore, ensure that you record such configuration changes. You might need this information to trace the port usage by a subscriber.
+ Ensure uniform port allocation uniform for all subscribers