Loading ...The new and improved Core Knowledge Simulation will be released in December 2009! Here are some more new questions you will find in the database.
1.00 Implement Layer 2 Technologies
You configured your switch (SWA) with the command spanning-tree vlan 26 root primary and you have confirmed the switch is the root bridge for VLAN 26. Later, another switch is introduced (SWB) that has a priority value for VLAN 26 set at 8192. What happens to the root bridge?
2.50 Implement IPv4 Enhanced Interior Gateway Routing Protocol (EIGRP)
What type of EIGRP route from the topology table can be used for load balancing through the use of the variance command?
2.60 Implement IPv4 Border Gateway Protocol (BGP)
Which open standard BGP attribute is used first in the BGP Best Path selection algorithm?
5.00 Implement IP Multicast
What device is used to dynamically announce the RP address to all routers in a PIM version 1 environment?
1.00 Implement Layer 2 Technologies
You configured your switch (SWA) with the command spanning-tree vlan 26 root primary and you have confirmed the switch is the root bridge for VLAN 26. Later, another switch is introduced (SWB) that has a priority value for VLAN 26 set at 8192. What happens to the root bridge?
If the SWB priority of 8192 is the lowest priority, this new switch becomes the root.
http://www.cisco.com/en/US/docs/switches/lan/catalyst3560/software/release/12.2_52_se/command/reference/cli3.html#wp1947142
2.50 Implement IPv4 Enhanced Interior Gateway Routing Protocol (EIGRP)
What type of EIGRP route from the topology table can be used for load balancing through the use of the variance command?
A feasible successor route.
http://www.cisco.com/en/US/docs/ios/iproute_eigrp/command/reference/ire_s1.html#wp1022904
2.60 Implement IPv4 Border Gateway Protocol (BGP)
Which open standard BGP attribute is used first in the BGP Best Path selection algorithm?
Local Preference
http://www.cisco.com/en/US/docs/ios/12_2/ip/configuration/guide/1cfbgp.html#wp1000898
5.00 Implement IP Multicast
What device is used to dynamically announce the RP address to all routers in a PIM version 1 environment?
The Auto-RP Mapping Agent
http://www.cisco.com/en/US/docs/ios/ipmulti/configuration/guide/imc_basic_cfg_ps6350_TSD_Products_Configuration_Guide_Chapter.html#wp1058990
Hi Anthony,
Thanks for the great questions/answers. I was using your answer links for further reading and noticed that the answer link for question 2.60 (bgp) is identical to the earlier eigrp answer link. That is ok as it forced me to look up the answer using the doc cd.
Thanks again and keep up the great work!
Hi Anthony,
thats great news… i hope it will be more helpful in studies.
When polymorphic labs will be upgraded to V4? is there any way to to generate polymorphic labs for only a specific technology?
Hi Nadeem!
I have not heard about Polymorphic lab developments, but I am sure Graded Labs is working on something special. I will try and find out something soon.
I was thrilled to hear about the new Core Knowledge Simulation – it will be the only tool like it in CCIE Training. Exciting stuff.
Hi Anthony,
Thanks for the OEQs.
Kindly help me to clarify first ques & answer
(1.00 Implement Layer 2 Technologies)
As per the Cisco Doc link provided, understand as follows.
When a new switch B is introduced with lower priority , Switch A will reduce the priority for the vlan to 4096 less than Switch B’s priortiy and maintain the root bridge status.
The feature will indeed force the root bridge election when you run it by setting the appropriate priority value. The issue here – is a switch might be introduced later with a lower priority value and take over. Understand this root priority setting is not a protection mechanism that works in the future.
Thanks Anthony.
Hi,
(1.00 Implement Layer 2 Technologies)
if SWB is introduced in the Lan with priority lower than Switch A with root configured and also if rootguard is enabled on sw A. how Sw A will react to superior bpdu sent by SWB ?
Will this help to maintain the elected root to stay root.?
Anthony had given all the answers thanks buddy.
The documentation is not quite clear on what the ’spanning-tree root primary’ command does. You should see it as a macro command that detects the current root BID value, and sets it’s own BID to 4096 less than that value.
If you’d enter the command in a switch, the current/startup config will not reflect the ‘root primary’ command, but instead shows ’spanning-tree priority xyz’.
hth.
Hi Anthony,
when is the 6 day 12 day new online class be posted for already subscribed user for the 5/10days older version?
thanks
Wooo, 4/4!
Thanks for the great examples.
I’m not so worried about OEC anymore.. I happen to be studying towards CCNP and this seems to be CCNA/P level stuff.
Will be using the provided links for additional reading too
Cheers,
Shane
Hi Anthony,
Thanks for the new questions!!
Just on that last point Saj made, I also thought that if you issued the “spanning-tree vlan 26 root primary” that the “ROOT PRIMARY” keywords were a macro which would always keep (SWA)as the ROOT switch in the topology???
Hi Ian!
Nope!
Check your running configuration after you issue the command – it is “macro” for setting the priority initially.
Hi Bmom – we need to add an online class for early next year and record it to update the 6/12 day.
I will make sure we announce the dates on the blog.
Hi Ronnie!
Excellent work – RootGuard is the tool that we use to help protect the root bridge placement. Remember, the RootGuard feature is a per port configuration.
Hi Anthony,
Thanks for that clarification!!!
I’m glad I saw that article now, Someone on a Video or an Audio lecture one time said that the Macro would continously lower it’s value to maintain Root Status! Did this used to be the case at one time?
When I checked it, you were right, the new switch took over Root status and the Macro Switch lost it’s Root Priority and never bothered trying to regain status!!
Thanks for that OEQ
Rgds,
Ian.
I wish you could release it now…lol. I am to take the lab in Dubai on the 6th of December
Hi Ian!
I have never seen the feature behave that way. I would assume someone was pointing out what the feature does upon INITIAL configuration.