Who Wins Flashcards
In Routing Protocol Metrics which route wins?
Lowest
In Routing Protocol Administrative Distances, which AD wins?
Lowest
In Spanning Tree, what determines the Root Bridge?
Lowest priority and the lowest base MAC address
In RIP what determines the Metric?
Hop Count
In OSPF what determines the Metric?
The sum of all Outgoing Interface Costs to get to the network.
In EIGRP what determines the Composite Metric?
Metric = (( 10^7 / least_bandwidth in Kbps ) + Cumulative Delay ) * 256
In Spanning Tree, which Bridge ID wins?
- Lowest priority in the BID first
- If priorities tie then lowest MAC address
In OSPF, which router becomes the Designated Router?
Router with the highest Priority, if a tie then highest Router ID
In OSPF, which router becomes the Backup DR?
BDR election also uses highest priority and then highest router-id.
When a new network segment is initialized the first election is for BDR. The elected BDR recognizes that there is not a DR and becomes DR and there is another election for a BDR.
When checking delay on an interface using the ‘show ip eigrp top’ command what unit of measure is delay in?
Microseconds
In order to use Delay in the EIGRP metric formula what must you before adding the Delay measurement?
Take Microseconds and Divide by 10.
In Spanning Tree, how is the root port determined?
Whichever port has the least OUTBOUND Interface Cost to get to the Root.
HSRP Active Router
Highest priority wins
Tie breaker - Highest IP address
In Spanning-tree, which Port Priority is better? Default is 128.
Lower is better.
LACP System Priority
Lowest
LACP Port Priority
Lowest
In an IGMP Querier Election
Lowest LAN interface IP address
In PIM when identifying the RPF interface, if 2 interfaces have the same AD and metric back to the source?
The interface with the highest IP address wins
in multicast, two PIM Forwarders on the same LAN
- lowest administrative distance
- lowest metric back to the source
- then highest IP address
Multiple PIM routers on the same subnet.
- Highest DR Priority value
- Tie breaker - Highest IP address on the subnet
Multicast with Auto RP when multiple C-RPs advertise themselves.
Highest IP address wins and becomes the active RP
C-BSR election
- Highest Priority
- If tie then C-BSR with highest IP address wins
PIM Routers run algorithm on BSR-provided Group-to-RP Mapping Cache to choose an RP. Which candidate wins?
- C-RP with the longest prefix match, if a tie then,
- C-RP with the Lowest Priority wins, if a tie then,
- C-RP with highest hash value, if still a tie then,
- The highest IP address wins
crypto isakmp policy [priority]
The lowest number wins. Lowest number possible is 1.
BGP neighbors both propose different HOLD times. Who wins?
The shortest HOLD time wins.
In QOS using the CS PHB with values CS0 thru CS7, which one gets better priority?
CS7 - the higher the CS the better the priority
For layer 2 QOS the Priority Code Point (PCP) using Class of Service with 8 levels
- CoS 0 is lowest and treated worst
- CoS 7 is highest and treated best
In Wireless, SNR (signal-to-noise ratio)
A larger SNR value is better. The larger the number the larger the gap is between the noise floor and the receiver’s sensitivity level
In Wireless, channel utilization
The lower the better
In Wireless, Signal Strength
Signal strength of -50 is better than -70
In Wireless, connection score
in percentage with 100% being the best
In Wireless, Received Signal Strength Indicator (RSSI)
-50 dBm is better than -70 dBm
BGP PA - Weight
Higher value wins
BGP PA Local Pref - lower or higher?
Higher is preferred
BGP Path Attribute - MED
The lower the MED the more preferred it is
In BGP who manages the connection during the Connect State
Router with the higher BGP router ID
BGP PA AIGP Metric
Lowest wins
BGP PA IGP metric to next hop.
Lowest wins
BGP PA Peer router ID
Lowest wins
BGP PA Peer IP address.
Lowest wins
Under ‘router ospf’ if an interface matches two network statements each specifying a different area which area/network statement is chosen?
The area with the longest matching network statement wins
If OSPF is configured directly on an interface plus the interface is included in a network statement under router OSPF which takes precedence?
The interface config trumps the network statement.
OSPF authentication: which key in the key chain will OSPF use to sign egress packets?
The key with the highest key ID
OSPF: Who wins when there are conflicting parameters between what is under the router process configuration and what is on the interface
Interface parameters take precedence
OSPF: when there is a conflict between what is directly under the “router ospf” command and what is under ‘address-family’
Address-family wins
OSPF: which Hello timer will IPv6 use in the following example:
interface gig0/0
ip address 10.1.1.0 255.255.255.0
ipv6 address 2001:DB8:0:12::2/64
ospfv3 10 hello-interval 11
ospfv3 10 ipv6 area 0
ospfv3 10 ipv6 hello-interval 10
ospfv3 10 ipv4 area 0
The Hello timer specified with the address family will take precedence over the Hello timer without an address family
In MPLS, which LDP neighbor gets the passive Server role?
The router with the lowest LDP ID
In BGP, which takes priority between conflicting statements in a BGP Peer Group and in a BGP neighbor statement.
BGP Neighbor Statement wins
In IPV6 First Hop Security Features - IPv6 Snooping, there are 2 policies, one for the VLAN and one for the interface. Which takes precedence?
The policy on the interface.
In OSPF, if the exact same route is advertised in Type 7 LSAs by 2 different ASBRs which route is preferred?
The route coming from the ASBR with the lowest Router ID.
