Misc - Exam A Flashcards
1
Q
What is the default administrative distance for eBGP?
A
20
2
Q
What is the default administrative distance for a EIGRP summary route?
A
5
3
Q
What is the default administrative distance for an IGRP route?
A
100
4
Q
What is the default administrative distance for an IS-IS route?
A
115
5
Q
What is the default administrative distance for an External EIGRP route?
A
170
6
Q
What is the default administrative distance for an iBGP route?
A
200
7
Q
What Transport layer protocol and port does DNS use?
A
TCP and UDP 53
8
Q
What Transport layer protocol and port does TFTP use?
A
UDP 69
9
Q
What Transport layer protocol and port does SNMP use?
A
UDP 161 and 162
10
Q
What Transport layer protocol and port does SMTP use?
A
TCP 25
11
Q
What Transport layer protocol and port does FTP use?
A
TCP 20 and 21
12
Q
What Transport layer protocol and port does POP3 use?
A
TCP 110
13
Q
What Transport layer protocol and port does Telnet use?
A
TCP 23
14
Q
What Transport layer protocol and port does DHCP use?
A
UDP 67 and 68
15
Q
What is the default reference bandwidth for OSPF?
A
100,000,000 (100Mbps)
16
Q
What OSPF network types have default Hello and Dead timers of 10 and 40 seconds?
A
Broadcast and Point-to-Point
17
Q
What OSPF network types have default Hello and Dead timers of 30 and 120 seconds?
A
Non-broadcast
Point-to-multipoint
18
Q
True / False: Point to Multipoint OSPF networks do not perform DR/BDR election
A
True
19
Q
What OSPF network types do send Multicast updates?
A
Broadcast
PPP
Point to Multipoint
20
Q
How would you set the OSPF network type?
A
ip ospf network {point-to-point}
21
Q
What IEEE standard is LACP?
A
802.3ad
22
Q
True / False: If two sides of a link configure different EtherChannel aggregation protocols for negotiation, the link will be formed anyway with the first configured one
A
False. The protocol must match on each switch
23
Q
What IEEE standard is LLDP?
A
802.1AB
24
Q
What Multicast destination address does LLDP use?
A
0180.C200.000E
25
What Multicast destination address does CDP use?
0100.0CCC.CCCC
26
How often are LLDP advertisements sent by default? What is the holdtime?
30 seconds
| 120 seconds
27
How often are CDP advertisments sent by default? What is the holdtime?
60 seconds
| 180 seconds
28
What is STP flapping on a port and what could be the cause?
Process repeats: root bridge selection, port role switch, port status migration. Convergence fails.
```
Link fault (cable, rate, duplex)
Node or network fault causing STP packets to not be sent, processed, or discarded
```
29
What IEEE standard is STP?
802.1d
30
What IEEE standard is RSTP?
802.1w
31
How would you enable RSTP?
spanning-tree mode rapid-pvst
32
What are the two port roles STP and RSTP have in common?
Designated port
| Root port
33
What are the two port roles that exist in RSTP that are not in STP?
Alternate
| Backup
34
What is the function of the Alternate port role in RSTP?
Provides a way for RSTP to quickly replace a switch's root port
35
What is the function of the Backup port role in RSTP?
Provides a way for RSTP to quickly replace a switch's designated port on a LAN
36
What does RSTP call the blocking state?
Discarding
37
What STP port states does RSTPs Discarding state replace?
Bocking
Disabled
Listening
38
What is the forward delay timer value for STP?
15 seconds
39
What is the reason for the forward delay time in STP?
At the same time all switches have been all told to time out their MAC table entries. When topology changes the existing MAC table entries may cause a loop.
Switches tell each other (BPDU) that topology has changed and to time out entries, but causes need to wait in listening and learning states (15secs each)
40
What does the Learning STP/RSTP state do?
Learns MACs but does not forward traffic
41
When can RSTP bypass the Learning state?
When it knows the transition wont create a loop because its using an Alternate port to replace the root port
42
What is the criteria to be an alternate port?
Both the Root port and the alternate port must receive Hellos that identify the same root switch
43
What is the criteria to be an alternate port?
Both the Root port and the alternate port must receive Hellos that identify the same root switch
44
What is the default STP priority?
32768
45
What values does RSTP use for Hello and Max Age timers?
2 seconds
| 3 x Hello for Max Age
46
What is STP root guard?
Prevent a new switch from being elected root by configuring Root guard on a switch port that you are connecting to a new unconfigured switch
47
How do you enable STP root guard feature on a given port?
spanning-tree guard root
48
What is BPDU guard used for?
Prevent loops on a port that could erroneously receive BPDUs (typically edge ports that have port fast enabled)
49
What are the three Port Security violation modes?
Protect
Restrict
Shutdown
50
Why should you avoid putting TCP and UDP traffic in the same class for QoS?
It can cause TCP starvation.
UDP traffic is not aware of packet loss due to congestion control mechanisms, so devices sending UDP traffic might not reduce their traffic rates, dominating the queue and starving TCP traffic
51
What is the Global TCP Synchronization problem and what can cause it?
Tail drop can cause it.
Global TCP Synchronization is when all TCP sources in a network reduce traffic flow during periods of congestion and then increase it after, triggering congestion again
52
What is WRED and what key problem does it address?
Congestion avoidance mechanism that addresses Tail Drop.
It allows you to configure different Tail drop thresholds for each IP precedence or DSCP value so that lower priority traffic is more likely to be dropped
53
True / False: In a cloud based network, APs are all autonomous
True.
| But they are managed and controlled centrally from the cloud
54
What are packets protected with when encryption is enabled for an AP connected to a WLC via CAPWAP?
Datagram TLS (DTLS)
55
Is trunk link needed for the VLANs supported by an AP connected via CAPWAP tunnel?
No.
| All VLANs its supports are encapsulated and tunneled as L3 IP packets, rather than individual L2 VLANs
56
What three general types of 802.11 frames are there?
Control
Data
Management
57
What is the 2 byte FC field for in the 802.11 header?
Frame Control field
Used to identify the type and sub-type of each frame
58
What is CCMP?
Cipher Block Chaining Message Authentication Code Protocol
59
What does WPA2 use for MICs and Encryption?
AES and CCMP
60
What does WPA use for MICs and Encryption?
RC4 and TKIP
61
What is TKIP?
Temporal Key Integrity Protocol
62
What is the IEEE standard for Ethernet?
802.3
63
What is GCMP?
Galois/Counter Mode Protocol
Used along with AES to provide MICs and encryption
64
What IEEE standard number covers WLANs?
802.11
65
How would you configure a voice and data VLAN on ports connected to phones?
switchport mode access
switchport access vlan 10
switchport voice vlan 11
66
How would you set allowed VLANs on a trunk?
switchport trunk allowed vlan 1-60
67
What hex do unique local unicast addresses always being with?
FC or FD
First 7 bits always 1111110
68
What is the overarching IPv6 prefix for Multicast communication?
FF00::/8
69
What is L3 security VPN Pass-Through?
Enables L3 security for WLANs by allowing a client to establish a connection with a specific VPN server
70
What is L3 security Web Authentication?
Enables L3 security for Guest LANs, prompting for username and password when client connects
71
What is L3 security Web Passthrough?
Enables direct access to the network for Guest LANs without prompting for a username and password
72
What is UplinkFast?
Increases convergence speed for an access layer switch that detects a failure on the root port with backup root port selection
73
What IEEE standard covers MST?
802.1s
74
What do you enable DAI?
ip arp inspection vlan
75
What is BackboneFast?
Increases convergence speed for switches that detect a failure on links that are not directly connected to the switch
76
What type of interface is the OSPF Non-broadcast network type enabled by default on?
X.25
| Frame Relay
77
What are some key differences PPP and HDLC?
HDLC is bit oriented but PPP is byte oriented
HDLC is proprietary
PPP provides auth
78
What is FDDI?
Fiber Distributed Data Interface
A LAN protocol that utilizes token passing media access method on a dual ring topology
Uses Fiber optic cables
Designed to run data across the network backbones of larger companies
79
What type of interfaces would enable the OSPF Point to Point network type by default?
PPP
| HDLC
80
What type of interfaces would enable the OSPF Broadcast network type by default?
Ethernet
| FDDI
81
What are VLANs 1002 - 1005 reserved for?
Token Ring and FDDI VLANs
82
How do you stop a port sending DTP messages?
switchport nonegotiate
83
What measures could you take to prevent VLAN hopping?
Disabling DTP on a port
Changing the native VLAN
Configuring user-facing ports as access ports
84
How would you finish configuring PAT using an ACL to select networks to be translated?
access-list 1 permit 192.168.1.0 0.0.0.255
| ip nat inside source list 1 interface FastEthernet0/0 overload
85
What Cisco AP mode offers a failsafe if the CAPWAP goes down?
FlexConnect mode
86
What is another name for a Hypervisor?
VMM (Virtual Machine Monitor)
87
What is a Distribution System and what is it used for?
It is the wired network used to connect APs together.
In a split MAC architecture the point where APs touch DS is moved upstream to the WLC instead
88
Why do Distribution System ports always operate in 802.1Q trunk mode?
Because the DS ports must carry data that is associated with many different VLANs
89
What is a LAG?
Link Aggregation Group bundle of Ethernet links
90
How do you encrypt older IOS passwords?
service password-encryption
91
What are the possible encryption level values you can pass into enable secret command?
0 for plain text
4 for SHA-256
5 for MD5
92
How many username commands are allowed for a given username?
Only one.
You cannot specify a password and a secret for a local login username
93
What are the range of HSRP group numbers?
0 - 255
Default is 0
94
What does a site-to-site VPN typically use to route and secure traffic?
GRE with IPSec
95
What is a fully specified static route?
Static route that defines all of
- Destination network
- Outbound interface
- Next hop IP
96
What is a recrusive static route?
A static route that specifies only
- Destination IP
- Next hop IP
97
What range of Ethernet MACs are reserved for IP multicast?
01-00-5E-00-00-00 - 01-00-5E-7F-FF-FF
98
Does `show cdp neighbors` show the IP address of the neighbor?
No
99
What info is display from `show cdp neighbors`?
```
Device ID of neighbor
Capabilities
Product number
Holdtime
Local interface
Remote interface
```
100
What is the Ethernet Type (EtherType) field for?
Identifies the type of network / L3 packet that sits inside the Ethernet frame
101
How do you configure port fast on a port or as default for all?
Interface:
spanning-tree portfast
Globally:
spanning-tree portfast default
Globally with BPDU Guard:
spanning-tree portfast bpduguard default
102
How do you enable BPDU Guard on an interface?
spanning-tree bpdu guard enable
103
What MIC and Encryption is used for WPA3?
GCMP with AES
104
Which OSPF network types have a default Hello timer of 10 seconds and default dead timer of 40 seconds?
Broadcast and Point to Point
105
Which OSPF network types allow Multicast updates?
Broadcast
Point to Point
Point to Multipoint
106
Which OSPF network types perform DR/BDR elections?
Broadcast
| Non-broadcast
107
What protocol and port does Puppet accept inbound requests from agents on?
HTTPS TCP 8140
