Answer: D 

Explanation: 

To disable sequence numbers, use the no service sequence-numbers global configuration command. 

This example shows part of a logging display with sequence numbers enableD. 000019: %SYS-5-CONFIG_I: Configured from console by vty2 (10.34.195.36) 

In this example we see the absence of sequence numbers on the log messages. 

Not A. In this example there are no time stamps or uptimes shown in the logs. 

Not B. The default buffer size is 4096 bytes. 

Not C. The logging level in this example is informational (level 6), which will display levels 0-6 in the logs. Warnings are level 4. 

Answer: A 

Explanation: 

Here we see that COS 3 is mapped to DSCP 46, which is the Expedited forwarding class: The Expedited Forwarding (EF) model is used to provide resources to latency (delay) sensitive real-time, interactive traffic. The EF model uses one marking -- DSCP 46. 

Answer: C 

Explanation: 

Example on how to deny all prefixes originated in Autonomous System 200 

router bgp 100 

neighbor 10.1.1.1 remote-as 65535 

neighbor 10.1.1.1 route-map map1 in 

! 

route-map map1 permit 10 

match as-path 1 

! 

ip as-path access-list 5 deny _200$ 

ip as-path access-list 5 permit .* 

Reference: http://www.cisco.com/c/en/us/td/docs/ios/termserv/configuration/guide/12_4t/tsv_12_4t_bo ok/tsv_reg_express.html 

Answer: A,D 

Explanation: 

In this example we can see that the s, T, and I flags are set. Here is a list of the flags and their meanings: 

show ip mroute Field Descriptions 

Field Description 

Flags: 

Provides information about the entry. 

D - Dense 

Entry is operating in dense mode. 

S - Sparse 

Entry is operating in sparse mode. 

B - Bidir Group 

Indicates that a multicast group is operating in bidirectional mode. 

s - SSM Group Indicates that a multicast group is within the SSM range of IP addresses. This flag is reset if the SSM range changes. 

C - Connected 

A member of the multicast group is present on the directly connected interface. 

L - Local 

The router itself is a member of the multicast group. 

P - Pruned 

Route has been pruned. The Cisco IOS software keeps this information so that a downstream member can join the source. 

R - RP-bit set 

Indicates that the (S, G) entry is pointing toward the RP. This is typically prune state along the shared tree for a particular source. 

F - Register flag 

Indicates that the software is registering for a multicast source. 

T - SPT-bit set 

Indicates that packets have been received on the shortest path source tree. 

J - Join SPT 

For (*, G) entries, indicates that the rate of traffic flowing down the shared tree is exceeding the SPT-Threshold set for the group. (The default SPT-Threshold setting is 0 kbps.) When the J- Join shortest path tree (SPT) flag is set, the next (S, G) packet received down the shared tree triggers an (S, G) join in the direction of the source, thereby causing the router to join the source tree. 

For (S, G) entries, indicates that the entry was created because the SPT-Threshold for the group was exceeded. When the J- Join SPT flag is set for (S, G) entries, the router monitors the traffic rate on the source tree and attempts to switch back to the shared tree for this source if the traffic rate on the source tree falls below the SPT-Threshold of the group for more than 1 minute. 

M - MSDP created entry 

Indicates that a (*, G) entry was learned through a Multicast Source Discovery Protocol (MSDP) peer. This flag is only applicable for a rendezvous point (RP) running MSDP. 

X - Proxy Join Timer Running 

Indicates that the proxy join timer is running. This flag is only set for (S, G) entries of an RP or "turnaround" router. A "turnaround" router is located at the intersection of a shared path (*, G) tree and the shortest path from the source to the RP. 

A - Advertised via MSDP 

Indicates that an (S, G) entry was advertised through an MSDP peer. This flag is only applicable for an RP running MSDP. 

U - URD 

Indicates that a URD channel subscription report was received for the (S, G) entry. 

I - Received Source Specific Host Report 

Indicates that an (S, G) entry was created by an (S, G) report. This (S, G) report could have been created by IGMPv3, URD, or IGMP v3lite. This flag is only set on the designated router (DR). 

Reference: http://www.cisco.com/c/en/us/td/docs/ios/12_0s/feature/guide/12s_ssm.html 

Answer: A 

Answer: A 

Answer: C 

Explanation: 

FIB TCAM Exception - If you try to install more routes than are possible into the FIB TCAM you will see the following error message in the logs: 

CFIB-SP-STBY-7-CFIB_EXCEPTION : FIB TCAM exception, Some entries will be software switched 

%CFIB-SP-7-CFIB_EXCEPTION : FIB TCAM exception, Some entries will be software switched. 

%CFIB-SP-STBY-7-CFIB_EXCEPTION : FIB TCAM exception, Some entries will be software switched. 

This error message is received when the amount of available space in the TCAM is exceeded. This results in high CPU. This is a FIB TCAM limitation. Once TCAM is full, a flag will be set and FIB TCAM exception is received. This stops from adding new routes to the TCAM. Therefore, everything will be software switched. The removal of routes does not help resume hardware switching. Once the TCAM enters the exception state, the system must be reloaded to get out of that state. You can view if you have hit a FIB TCAM exception with the following command: 

6500-2#sh mls cef exception status 

Current IPv4 FIB exception state = TRUE 

Current IPv6 FIB exception state = FALSE 

Current MPLS FIB exception state = FALSE 

When the exception state is TRUE, the FIB TCAM has hit an exception. 

The maximum routes that can be installed in TCAM is increased by the mls cef maximum-routes command. 

Reference: https://supportforums.cisco.com/document/59926/troubleshooting-high-cpu-6500-sup720 

Answer: C 

Explanation: 

The example below shows how to configure EIGRP HMAC-SHA2 on Cisco router: 

Device(config)# router eigrp name1 

Device(config-router)# address-family ipv4 autonomous-system 45000 

Device(config-router-af)# af-interface ethernet 0/0 

Device(config-router-af-interface)# authentication mode hmac-sha-256 0 password1 

Device(config-router-af-interface)# end 

Reference: http://www.cisco.com/c/en/us/td/docs/ios-xml/ios/iproute_eigrp/configuration/15-sy/ire-15-sy-book/ire-sha-256.html 

Answer: C,D 

Explanation: 

Even though R4 is the active HSRP router, traffic will flow through R5 and only R5 will send the join messages. The Multicast DR is elected by the higher IP address or priority. R5 has 192.168.2.2 and R4 has 192.168.2.1. R5 is the DR which sends all packets to the RP. 

Answer: