Refer to the exhibit. What does the command channel-group 1 mode desirable do? *
A.
enables LACP unconditionally
B.
enables PAgP only if a PAgP device is detected
C.
enables PAgP unconditionally
D.
enables Etherchannel only
E.
enables LACP only if a LACP device is detected
channel-group [#] mode desirable (use PAgP in an active mode, it will start to send PAgP packets)
I think B is correct. On page 103 of CCNP-Switch Foundation Learning Guide, it shows 4 combinations of PAgP settings. The 2nd & 3rd combinations use “desirable” mode, but a channel is formed in only 1 case, so it is not unconditional.
C answer is correct
example:
http://www.cisco.com/en/US/products/hw/switches/ps5304/products_configuration_guide_chapter09186a008007f33a.html
It is a trick question, anwser C is correct.
Anwser C is not saying to enable trunking unconditionally.
Anwser C is saying that the PAgP protocol is enable unconditionally, which is true, PAgP is on unconditionally and always looking to form a trunk.
tha answer correct is C!!!!
ssigns the Fast Ethernet or Gigabit Ethernet interfaces to the EtherChannel with the channel-group command. The channel number must be the same channel number you assigned to the EtherChannel interface.
Configures PAgP parameters on the channel-group to automatically create FEC and GEC links. To issue the PAgP parameters issue, the mode command. The three configurable modes follow:
auto enables PAgP only if a PAgP device is detected.
desirable enables PAgP unconditionally on EtherChannel enabled ports.
on forces the port to form a channel.
For a detailed description of the command modes, see Table 7-1.