BPG 3.0 Flashcards
Q
A
Which feature is equivalent to soft configuration inbound?
route refresh
What is the difference between route-refresh and soft reconfiguration inbound?
soft reconfiguration creates a database per neighbor, route refresh does not
Feature that allows informing the neighbor which prefixes will be filtered so that these prefixes are not sent
Outbound route filter neighbor 10.0.255.9 capability orf prefix-list both
Consider a router without a peer group with 150k routes and 3 peers, how many NRLI should be generated?
450k
Feature that allows neighbors with the same outbound policies to be grouped automatically.
dynamic groups
A neighbor can only inherit configurations directly from one session template but indirectly from up to 7
true
A session template will inherit configurations from only other N session templates
false, a session template inherits configurations from only one other session template
A policy template will inherit configurations from only other N policy templates
true
A route received in an RR from an RR Client will be announced to other RR Clients and to other iBGP peers
true
A route received in an RR from an iBGP Peer will be announced to other RR Clients and to other iBGP peers
false, it will be announced to other RR Clients but not to other iBGP peers
In a confed scenario, the next_hop attribute is changed when a prefix is announced between SubASes
false, it is not modified
In a confed scenario, the local_pref attribute is maintained when a prefix is announced between SubASes
true
In a confed scenario, the med attribute is maintained when a prefix is announced between SubASes
true
The AS_CONFED_SEQUENCE attribute is equivalent to which other attribute?
AS Path
The shorter AS_CONFED_SEQUENCE influences the choice of the best path within a Confed AS
false
Within which option of the TCP header does the MD5 hash of the BGP update go?
option 19
MD5 hash also is calculated over IP and TCP headers, BGP authentication will work over devices performing Network Address Translation (NAT) or Port Address Translation (PAT)
false, will not work
Whenever a password is configured, BGP sessions must be restarted
false, if the password configuration is done on both sides within the 180-sec window, there is no need to restart.
In which method RTBH source or destination is uRPF combined with blackhole?
source
Which feature is used to reduce processing caused by unstable routes
route flap dampening
Which parameter of route dampening refers to the time interval in which the penalty falls by half?
half-life, 15 min
Which parameter of route dampening limits the point at which the route becomes suppressed?
Suppress limit, 2000
What is the default interval for BGP keepalives
60 secs
What is the interval between BGP scan executions
60 secs
What is the advertisement timer for eBGP and iBGP neighbors?
30 secs and 0
even if the IP routing table indicates that the neighbor is no longer reachable, BGP will not trigger the convergence process until the BGP session hold-down timer expires.
true
BGP convergence can also be improved to some extent by configuring a larger scan time interval for the BGP scanner process, configuring a larger advertisement interval between BGP neighbors, configuring smaller keepalive and hold-down timers.
false. BGP convergence can also be improved to some extent by configuring a smaller scan time interval for the BGP scanner process, configuring a smaller advertisement interval between BGP neighbors, configuring smaller keepalive and hold-down timers.
Complete: ___________ is an optimization technique available on Cisco ____ Software platforms. characteristics: Supported on Cisco _____ Software only, splits BGP functionality into three process types with several instances: BGP process manager (one instance) BGP RIB process (one instance per address family) BGP speaker process (up to 15 instances) Used to reduce the impact that a fault in one address family has on another address family Must be enabled
Distributed BGP, IOS XR
Distributed BGP is used to reduce the impact that a fault in one address family has on another address family,
true
____ ______ is a method for maximizing the use of available bandwidth in the network between the endpoints of a TCP connection.
PMTU discovery
The default TCP MSS for BGP traffic is____ bytes. Enabling path MTU discovery, and thus using a higher MSS for BGP traffic, can improve BGP convergence because____ packets are required to send BGP updates.
536, fewer
The default input hold queue is platform-dependent and is __ on Cisco IOS Software platforms and____ on Cisco IOS XE Software platforms. Setting the length of an interface to 1000 will normally resolve problems that are caused by input queue drops of TCP ACKs.
75, 375
What command increases the size of the input queue to avoid drops during BGP update exchanges?
R2(config-if)#hold-queue 1000 in
BGP dynamic neighbors are configured using a range of IP addresses and BGP peer templates.
False. BGP dynamic neighbors are configured using a range of IP addresses and BGP peer group.
Commands that configure dynamic peers, limited to 200 peers, and for a range of 172.16.0.0/24
bgp listen limit 200 bgp listen range 172.16.0.0/24 peer-group IX-PEERS
Origin code: Egp > igp > incomplete
False Igp > egp > incomplete Na pratica igp > incomplete
Feature that allows installing two or more routes as best in the BGP table
Bgp multi path
Bgp multipath by default does not consider prefixes from different ASNs as eligible for multipath
true
Bgp add path is a capability
true
Bgp multi path allows a route reflector to announce two or more routes
false, that is the add path
