Tshoot Notes: Layer 2 Commands

VLANs
#show vlan
#show vlan id XX
#show vlan brief

DTP - dynamic trunk protocol
#show int trunk
# show int fa0/1 switchport | ex private|unknown

Troubleshooting VTP
#show cdp neighbors
#show int trunk
#show vlan brief | exclude 100
#show vtp status
#show vtp password

Troubleshooting STP
#show spanning-tree vlan 200
#show spanning-tree vlan 200 bridge
#show spanning-tree vlan 200 root
#show spanning-tree vlan 200 summary
#show spanning-tree vlan 200 details

Troubleshooting MSTP
#show spanning-tree mst 1
#show run | begin spanning tree
#show run | inc priority

Troubleshooting Etherchannel
#show int po1 switchport
#show etherchannel summary
#show int trunk#show spanning-tree vlan 10
#show cdp neighbors
#show run | inc FastEthernet|channel-group

Tshoot Notes: Layer 2 Technologies

VLANs 

- Layer 2 Broadcast Domain
- Data VLAN
- Voice VLAN (Auxilliary VLAN)
- VLAN1: default VLAN, Trunk Link - Native VLAN (untagged)
- Extended Range VLAN 1006 - 4094
- Extended Range VLANs prerequisite is VTP Transpartent mode

conf t
switchport mode access to configure for port access
switch access vlan 100 to assign vlan
switchport voice vlan XXX to assign voice vlan

#show vlan
#show vlan id XX
#show vlan brief

 TRUNK

- ISL
- 802.1Q - takes the frame and inserts a tag (a field of VLAN ID) + (a field for QOS)
- 802.1Q Native VLAN - VLAN1 (untagged)

DTP - dynamic trunk protocol

1. Categorize switches from core, access
2. Core switch will be dynamic desirable - forms trunk links
3. Access switch dynamic auto - auto forms with desirable

#switchport mode access dtp is off not for trunking
#switchport mode trunk dtp is on
#switchport mode dynamic desirable - will be trunk
#switchport mode dynamic auto - will be trunk if other side is desirable
#switchport no negotiate - turing off dtp process (can be use with either mode access or mode trunk)

[Does not work]
SW1
int fa 0/2
switchport trunk encap dot1q
switchport mode dynamic auto
SW2
int fa 0/2
switchport trunk encap dot1q
switchport mode dynamic auto

 [Trunking will work]
SW1int fa 0/2
switchport trunk encap dot1q
switchport mode dynamic desirable
SW2
int fa 0/2
switchport trunk encap dot1q
switchport mode dynamic auto

[Trunking will work - you need to try!]
SW1
int fa 0/2
switchport trunk encap dot1q
switchport mode trunk
switchport mode dynamic auto
SW2
int fa 0/2
switchport trunk encap dot1q
switchport mode trunk

[Trunking will work]
*Not having the same native vlan
SW1 - native vlan 10
SW2 - native vlan 20
[But will have inconsistencies if one of the VLAN20 is not same on SW1]


changing native vlan on other side
int fa 0/2
switchport trunk native vlan 20


[Trunking will work]
SW1
int fa 0/2
switchport trunk encap dot1q
switchport mode trunkswitchport nonegotiateSW2
switchport trunk encap dot1q
switchport mode trunk
switchport nonegotiate

[Will not work]
SW1
switchport trunk encap dot1q
switchport mode trunk
switchport nonegotiate SW2
int fa 0/2
switchport trunk encap dot1q
switchport mode trunk
switchport mode dynamic desirable

Things to remember for TRUNKING
1. Encapsulation mismatch
2. Native VLAN mismatch
3. Layer 1 - port shutdown
4. DTP misconfiguration
5. VTP and DTP relationships

#show int trunk
# show int fa0/1 switchport | ex private|unknown


 Troubleshooting VTP

VLAN Trunking Protocol = VLAN Management
VTP only works with trunks
To propogate VLAN information trunk links must be working

VTP Modes
1. Server - create and manage VLAN devices, propagate to servers and client
2. Client - slave to vtp server, cannot create and edit
3. Transparent - partipate in vtp domain, forward advertisement, not propagated
4. VTP off mode

#show vtp status - configuration revision

VTP Scenarios
1. Trunk
    - port are in access mode
    - incorrect vtp name
2. Domain Name / Password
    - mismatch vtp name --> change the vtp domain
    - mismatch password --> change the password
3. Overwrite versions
    - new swtich has higher revision --> change first to transparent
    - rename vtp domain
4. VTP version no 1 or 2
    - mismatch vtp version

#show cdp neighbors
#show int trunk
#show vlan brief | exclude 100
#show vtp status
#show vtp password

Changing VTP Domain Name (resetting revision numbers)
conf t
vtp domain Boyformat

Troubleshooting STP

1. 802.1D - IEEE
2. 802.1W - RSTP (rapid spanning tree protocol) - enable rapid PVST+
3. 802.1S - MSTP (built in behavior of RSTP)

STP Process
         
            dp        1GB     rp
[ SW1 ] --------------- [ SW4 ]
     |  rp                   nd |
     | 1GB                     | 100 MBPS 
     |  dp                  dp  |
[ SW2 ] --------------- [ SW3 ]
    RB dp         1GB     rp

1. Root Bridge - lowest bridge ID = Priority ID + VLAN ID + Lowest MAC Add
2. Non Root Bridge has a 1 Root Port (bandwidth higher)
3. Each Link has a Designated POrt
4. Non Designated Port

         
            dp        1GB     rp
[ SW1 ] --------------- [ SW4 ]
     |  rp                   nd |
     | 1GB                     | 100 MBPS 
     |  dp                  dp  |
[ SW2 ] --------------- [ SW3 ]
    RB dp         1GB     rp
1. Root Brige - Bridge Priority - Priority (Manual)
                                                  - Root Primary
2. Root Port - Manipulate Cost
3. Designated Port - Manipulate Cost

STP Toolkit
1. PortFast -
2. BPDU Guard -
3. Root Guard - superior bridge, no one can come in with lower priority
4. Loop Guard - stop normal convergence of STP

#show spanning-tree vlan 200
#show spanning-tree vlan 200 bridge
#show spanning-tree vlan 200 root
#show spanning-tree vlan 200 summary
#show spanning-tree vlan 200 details

1. Cost - Root
2. Bridge ID

1. Check for Bridge IDs
2. Check the Priorities

Troubleshooting MSTP


PVST - per vlan spanning tree - each vlan has its own topology
MST - 802.1S can implement only the exact numbers of topology
         - coexist with PVST

Fool-proof MST
1. Region Name
2. Revision Number
3. Instances - VLAN

#show spanning-tree mst 1

#show run | begin spanning tree
  - validate the region name (case sensitive)
  - revision number
  - instance

#conf t
#spanning-tree mst configuration
#name NAME OF REGION
#end

#conf t
#spanning-tree mst 1 root primary - manipulating priority
#spanning-tree mst 1 root secondary - backup

#show run | inc priority

Troubleshooting Etherchannel

Can be Layer 2 or Layer 3 (multilayer switches)

1. Shutdown the other side (to prevent err-disable)
    - err-disable sometimes require to make the configuration to default
2.  Both devices links are physically identical
3. Dynamic or Manual creation (ON:static / LACP: active, passive / PAGP: Auto,des)

#show etherchannel ? alot of verification commands

Creating etherchannel
1. Default the interfaces
#conf t
#default int range fa 0/1-6
#int range fa 0/1-6
#shutdown
#do show int status | include disabled
#switchport trunk encapsulation dot1q
#switchport mode trunk
#switchport trunk allowed vlan 10,20,30
#switchport trunk allowed vlan add 40 - additional vlan
#channel-group 1 mode active - LACP

#show int po1 switchport
#show etherchannel summary - show the ports on the bundle
#show int trunk#show spanning-tree vlan 10 (Cost 4 = 1000 / Cost 19 = 100)

#show etherchannel load-balance

2. Load Balancing
#conf t
#port-channel load-balance ? - shows the options/method for load balancing

#show cdp neighbors
#show etherchannel summary
#show int po1 switchport
#show run | inc FastEthernet|channel-group

Routing Notes 10 BGP

BGP DEFINITIONS

1. Reliable updateds require port 179 tcp based
2. Triggered updates only (5 Seconds internal and 30 seconds external)
3. Complicated metric for finding the best route
4. All neighbors are manually set up
5. Complex filters are typically used
6. The routing protocol of the internet
7. Management of trust and untrust
8. Routing through autonomous systems instead of routers
9. The slowest routing protocol
10. Primarily service provider, but also enterprise customer

BGP NEIGHBOR FORMS

Neighbors never discover each other, manual configuration is needed
Neighbor must be reachable on TCP179
Multiple Sessions to the same neighbor not permitter - DROP

Routing Notes 09 PATH CONTROL

POLICY BASE ROUTING

Configuring Policy Routing

conf t
ip access-list standard TAMAD
permit host 192.168.1.20
ip access-list extended PAGILAS
permit tcp host 192.168.1.21 any eq 23
permit tcp host 192.168.1.21 any 443
configuring access-list

route-map CORP_POLICY permit 10
match ip address TAMAD
set ip next-hop 201.1.1.2

show route-map

route-map CORP_POLICY permit 20
match ip address PAGILAS
set ip next-hop 200.1.1.2

show route-map

route-map CORP_POLICY permit 30
set ip next-hop 201.1.1.2
after policy 10 and 20 traffic will go to policy 30

int fa0/0
ip policy route-map CORP_POLICY
incoming traffic on this interface

IP-SLA

Measuring service levels on a particular circuit
Send probes (Ping, FTP, HTTP, DNS Lookup etc) to specific IP Address

Creating SLA Monitor Probe

conf t
ip sla monitor 1
type echo protocpl ipIcmpecho 200.1.1.2
timeout 500
how long to consider a ping lost
frequency 1
threshold 800
how long to consider it down
ip sla monitor schedule 1 start time now life forver

Modify your routing must create a track object consider a probe UP or DOWN

Creating a Track Object

conf t
track 1 rtr 1
rtr = response time reporter

Adding a track object on the route

ip route 0.0.0.0 0.0.0.0 200.1.1.2 track 1
ip route 0.0.0.0 0.0.0.0 200.1.1.2 50

Routing Notes 08 REDISTRIBUTION

PROCESS OF REDISTRIBUTION

1. Routing to be redistribute INTO the Router

To redistribute OSPF

conf t
Router RIP
redistribute OSPF

To redistribute EIGRP
conf t
Router OSPF
redistribute EIGRP

Redistribution Issues
2. Sub Optimal Routing
3. Routing Loops

Work Around for Redistribution

1. Tweek Administrative Distance in OSPF
2. Route Tagging to allow and block
3. Prefix List to allow and block
4. Access-list to allow and block

BASIC ROUTE REDISTRIBUTION

RIP-----------RT1-----------RT2-----------RT3--------OSPF
10.1.1.0/24     172.16.1.0/24   172.16.2.0/24     172.17.1.0/24
10.1.2.0/24                                                          172.17.2.0/24
10.1.3.0/24                                                          172.17.3.0/24
10.1.4.0/24                                                          172.17.4.0/24
10.1.5.0/24                                                          172.17.5.0/24
10.1.6.0/24                                                          172.17.6.0/24

Router 2
conf t
router rip
redistribute ospf 1 metric 5
or

conf t
router rip
redistribute ospf 1
default-metric 5

Router 1
show ip route

Router 2
conf t
router ospf
redistribute rip metric 100 subnets metric-type [1 or 2] 2
1 external type 1 metric - adding the cost of links
2 external type 2 metric - shows the same metric of 100
Router 3
show ip route

REDISTRIBUTION WITH DISTRIBUTION LIST

Filtering 2 Statements
RIP-----------RT1-----------RT2-----------RT3--------OSPF
10.1.1.0/24    172.16.1.0/24    172.16.2.0/24    172.17.1.0/24
10.1.2.0/24                                                        172.17.2.0/24
10.1.3.0/24                                                        172.17.3.0/24
10.1.4.0/24                                                        172.17.4.0/24
10.1.5.0/24                                                        172.17.5.0/24
10.1.6.0/24                                                        172.17.6.0/24

Router 2
conf t
access-list 1 permit 172.17.1.0 0.0.0.255
access-list 1 permit 172.17.2.0 0.0.0.255

router rip
distrubute-list 1 out

Router 1
show ip route
clear ip route
show ip route

Router 2
conf t
access-list 2 deny 10.1.1.0 0.0.0.255
access-list 2 deny 10.1.2.0 0.0.0.255
access-list 2 deny 10.1.3.0 0.0.0.255
access-list 2 deny 10.1.4.0 0.0.0.255
access-list 2 permit any

router ospf 1
distribute-list 2 out

Router 3
show ip route
clear ip route
show ip route

REDISTRIBUTION WITH PREFIX LIST

1.Alternative for access-list (Matching Routes)
- Improve Processor Utilization
- Better subnet mask matching abilities
2. 2 stage matching network and subnet mask
3. Similar to ACL

ip prefix-list ABA permit 172.30.0.0/16 ge 20 (ge=greater than)

a. 172.30.1.0/24 OK
b. 172.30.0.0/16
c. 172.30.32.0/19
d. 172.16.0.0/18
e. 172.30.10.0/24 OK

ip prefix-list ABA permit 172.30.0.0/16 le 20 (le=less than)

a. 172.30.1.0/24
b. 172.30.0.0/16 OK
c. 172.30.32.0/19 OK
d. 172.16.0.0/18
e. 172.30.10.0/24

REDISTRIBUTION WITH ROUTE-MAPS

2. Peform a series of IF > then statement called match/set
1. Order list of statements similar to Access-list
3. Typically used for:
- modify bgp attributes
- policy routing
- route filtering

ROUTER 2
conf t
router rip
redistribute ospf 1 metric 5 subnets

ROUTER 1
show ip route

ROUTER 2
conf t
access-list 5 permit 10.1.1.0 0.0.0.255
access-list 5 permit 10.1.2.0 0.0.0.255
access-list 5 permit 10.1.3.0 0.0.0.255
access-list 6 permit 172.17.1.0 0.0.0.255
access-list 6 permit 172.17.2.0 0.0.0.255
access-list 6 permit 172.17.3.0 0.0.0.255

route-map ABA permit 10
match ip address 5
exit

show route-map

route-map
set metric 1000
show route-map

router ospf 1

ROUTER 2
conf t
router ospf 1
redistribute rip route-map ABA subnets

ROUTER 3
show ip route

ROUTER 2
route-map ABA permit 20
set metric 500

ROUTER 3
show ip route

REDISTRIBUTION WITH PREFIX-LIST

Router 3
conf t
ip prefix list ABA permit 10.0.0.0/8
ip prefix list ABA permit 10.0.0.0/8 le 24
router ospf 1
redistribute rip metric 100 subnets

route map RM permit 10
match ip address prefix list ABA

match ip address prefix list ABA
match ip address prefix list ABA2
match ip address prefix list ABA3
or
match ip address prefix list ABA ABA2 ABA3

router ospf 1
redistribute rip metric 100 subnet route-map RM

Router 3
show ip route

Routing Notes 07 OSPF Design

BASICS

1. All areas must be connected to AREA 0 (backbone)
2. All routers in an area have the same topology table
3. Objective is to localize the updates within the area
4. Requires a hierarchical design
5. Runs on DIJKSTRA SPF algorithm

OSPF Router Types:
1. Area Border (ABR) - Summarize Routes
2. ASBR (Autonomous System Boundary Router) - Bridges outside world

Virtual Links - OSPF VPN Tunnel / acts as directly connected to AREA 0

OSPF Tables
1. Neighbor - provides the list of all routers forms relationship
2. Topology - provides the best route, second best route, roadmap of the network
3. Routing - consolidates the routes

OSPF NEIGHBOR RELATIONSHIPS

1. Determine the Router ID (loopback address is the highest)

2. Add interface to the LS database (dictated by network command)
    - Hello
    - Adverstise the network to other routers

3. Sends Hello messages on chosen interfaces
    - 10 seconds on broadcast
    - 30 seconds on nbma networks
    - contains all information
       Router ID
       Hello and Dead Timers*
       Network Mask*
       Area ID*
       Neighbors
       Router Priority
       DR / BDR IP Address
       Authentication Password*
       * - all must match to have neighbor relationship

4. Recives Hello
    - Check Hello / Dead Interval
    - Check Netmasks
    - Check Area ID
    - Check Authentication Passwords

5. Send Reply Hello
    - Check if new neighbor or old
    - Old - will reset the dead timers

6. Master - Slave Relationship Relationship
    - Determined by Priority Router-ID Breaks Tie
    - Higher Router ID becomes the master
    - Master sends description DBD packet
    - Slave sends its DBD packet

7. DBD are acknowledged and reviewed
    - Slave request details - LSR
    - Master sends updates - LSU
    - Master request details - LSR
    - Slave sends updates - LSU

8. Neighbors are synchronized
    - Full State


1. ------HELLO----]       Init
2. [----HELLO------       Init
3. --------DBD------]      Exstart
4. [------DBD-------       Exchange
5. --------LSU-------]      Loading
6. [------LSR--------       Loading
7.    FULL STATE

OSPF NEIGHBOR STATES

1. Down - No hello packets
2. Attempt - used for manual configured neighbors
3. Init - hello packet recived
4. 2 way state - identifies compatible neighbors
5. Exstart/Exchange - master slave relationship and DBDs exchange
6. Loading - Beautiful dance of LSR / LSA / LSU
7. Full - OSPF

DR -  provides update to the whole topology
BDR - provides update to the whole topology
Both manage neighbor relationship per conneciton
Must be elected to make sure all updates are reach in the topology

224.0.0.6 - Multicast Message for updates/connections
224.0.0.5 - Multicast Message by DR

OSPF METRIC

Cost = 100 / BW-IN-MBPS

Common Cost
56K = 1785
64K = 1562
T1 (1.544) = 65
E1 (2.048) = 48
Ethernet = 10
Fast Ethernet = 1

router ospf
auto-cost reference-bandwidth

SUMMARIZATION ON ABR AND ASBR

ABR Configuration

ROUTER 2
router ospf 1
router-id 2.2.2.2
network 172.16.1.0 0.0.0.255 area 0
network 172.16.2.0 0.0.0.255 area 1

show ip ospf neighbors

area 0 range 10.1.0.0 255.255.248.0
route summarization
area 1 range 10.2.0.0 255.255.248.0
route summarization

show ip route

ASBR Configuration

ROUTER 1
router rip
version 2
no auto summary
network 10.0.0.0
network 172.16.0.0

ROUTER 2
router rip
version 2
no auto summary
network 172.16.0.0

router ospf 1
redistribute rip metric 20 subnets
summary-address 10.2.0.0 255.255.248.0


OSPF SPECIAL AREAS

Backbone Area
LSA Type 1: Router LSA

Standard Area
LSA Type 2: Network LSA (DR Generated)

Stub Area
LSA Type 3: Summary LSA (ABR Summary Route)
- doesnt accept external network

Stub Network 
conf t
router ospf 1
area 23 stub

ABR
conf t
router ospf 1
area 23 stub

Totally Stubby Area
LSA Type 4: Summary LSA (ASBR Location)
- doesnt accept internal network
- doesnt accept external network

Stub Router
conf t
router ospf 1
area 45 stub

ABR
conf t
router ospf 1
area 45 no summary
Not-so-Stubby Area

LSA Type 5
External LSA (ASBR Summary Route)

OSPF VIRTUAL LINKS

Router with 2 Endpoints - Transit Area

[Router 1] -----(transit area)-------[Router 2]-----[Router3]

Router 2
router ospf 1
area 67 virtual-link 6.6.6.6

Router 1
router ospf1
area 67 virtual-link 7.7.7.7

show ip ospf virtual-links
Runs on Demand Circuit

Router 3
show ip route

OSPFv3

Routing Notes 05 EIGRP 3 Stub LB

EIGRP STUB NETWORKS

Stub is a feature to define a device as a dead end (not require to query)
Stubs dont go anywhere

Pre requisite: Configure EIGRP network for 2 devices
                      Enable debug for EIGRP

ROUTER 2
conf t
router eigrp XXX
eigrp stub

ROUTER 1
show ip eigrp neighbor details
to verify the stub network

EIGRP LOAB BALANCING

Pre requisite: Enable EIGRP for 3 routers
                      Make all three devices are neighbors
                      One of the device must be connecting to the other 2 routers

EQUAL: Must have equal cost load balancing - similar bandwidth for 2 or more links 

TO MAKE IT UNEQUAL: change the bandwidth or by variance command (multipier)

ROUTER1
conf t
router eigrp 100
variance 2
it will multiply the metric of the successor

to verify:
show ip eigrp topology

Routing Notes 06 EIGRP MPLS Design

EIGRP OVER MPLS

MPLS
1. service provider technology
2. creates labels (MPLS) for customers
    - improves routing speed
    - customer categorization/tagged of routing information
3. any physical media before going to service provider network (cable, dsl, eth etc)
4. L2 - layer 2 medium acts as a switch (not scalable)
5. L3 - layer 3 works as peering/neighbor with the customer
6. L2 - design perspective is too chaotic, work around are VLANs
7. L3 - BGP routing is used internally by the service provider, integrates with the tag
8. L3 - runs BGP natively with the customer
9. L3 - provides QOS

EIGRP OVER FRAME RELAY

Frame Relays
1. Dedicated circuits
2. DLCIs (Data Link Connection Identifier) , PVCs (Permanent Virtual Cirtuits)
3. Provisiongs bursting
4. Frame Relay Maps

PVC Designs
1. Hub and Spoke - one single point of failure
2. Full Mesh - interconnected PVCs
3. Partial Mesh - some sites are not interconnected

Multipoint Interface design for EIGRP
- Split Horizon occurs (interface cannot recieve an update, distance vector type)
- Hub and spoke behavior
- Manual mapping

Point to Point design for EIGRP
- Create a sub-interface
- Dedicated interface
- One manual neighbor statement removes multicast

EIGRP handles Non Broadcast Multi-Access (NBMA)

EIGRP Configuring Point to Point Configuration MPLS
- Creates a sub-interface per connection acting as its own subnet

ROUTER MAIN
conf t
int s0/0
encapsulation frame-relay
int s0/0.102 point-to-point
ip address x.x.102.1 255.255.255.252
frame-relay interface-dlci 102
int s0/0.103 point-to-point
ip address x.x.103.1 255.255.255.252
frame-relay interface-dlci 103

show ip interface brief
(interface would be done due, requires configuration on other router)

ROUTER-E 2
cont f
int s0/0
encapsulation frame-relay
int s0/0.201 point-to-point
ip address x.x.102.1 255.255.255.252
frame-relay interface-dlci 201
show ip interface brief

ROUTER-W 3
cont f
int s0/0
encapsulation frame-relay
int s0/0.301 point-to-point
ip address x.x.103.1 255.255.255.252
frame-relay interface-dlci 301
show ip interface brief

ROUTER MAIN, 2 and 3
router eigrp 55
no auto
network x.x.x.x

Next is to do summarization

ROUTER-W 3
conf t
int s0/0.301
ip summary-address eigrp 55 x.x.x.x y.y.y.y

ROUTER-W 2
conf t
int s0/0.201
ip summary-address eigrp 55 x.x.x.x y.y.y.y

ROUTER MAIN
show ip route

EIGRP Configuring Multipoint Configuration MPLS

ROUTER MAIN
conf t
int s0/0.100 multipoint
ip address 100.10.50.10 255.255.255.0
frame-relay map ip 100.10.50.20 102 (local DLCI) broadcast (disable non broadcast multi access/pretend broadcast is allowed)
frame-relay map ip 100.10.50.30 103 broadcast

ROUTER-W 2
conf t
int s0/0.201 multipoint
ip address 100.10.50.20 255.255.255.0
frame-relay map ip 100.10.50.10 201 broadcast
frame-relay map ip 100.10.50.30 201 broadcast (from RMAIN it will travel to RE3)

ROUTER-E 3
conf t
int s0/0.301 multipoint
ip address 100.10.50.30 255.255.255.0
frame-relay map ip 100.10.50.10. 301 broadcast
frame-relay map ip 100.10.50.20 301 broadcast (from RMAIN it will travel to RW2)

ROUTER MAIN, 2 and 3
router eigrp 100
no auto
network x.x.x.x

ROUTER MAIN
conf t
int s0/0.100
no ip split-horizon eigrp 100 (disbaling split horizon)

ROUTER MAIN, 2 and 3
show ip route

Routing Notes 02 EIGRP 2 SECURITY

EIGRP Routes and Security

Route Summarization

172.40.0.0/24
172.40.1.0/24
172.40.2.0/24
172.40.3.0/24
172.40.4.0/24
172.40.5.0/24
172.40.6.0/24
172.40.7.0/24  -- 172.40.0.0/21
172.40.8.0/24  --------------------- 172.40.0.0/20

ip summary-address eigrp 172.40.0.0 255.255.248.0
can be configure to an interface
specific routes will be disappered

interface s0/0
ip summary-address eigrp 172.40.0.0 255.255.248.0

Route Security

1. router eigp 10
2.1 passive-interface s0/0
will not send packets to establish eigrp connection

or

2.2 passive-interface default
will not send packets to establish eigrp globally

or

2.3 no passive-interface s0/0
turn on sending packets

Authentication = hashing not encryption

Router A
1. conf t
2. key chain joseph
3. key-string flower
4. accept-lifetime 2:0:0

Router B
1. conf t
2. ip authentication mode eigrp 10 md5
3. ip authentication key-chain eigrp 10 joseph

Routing Notes 01 EIGRP 1 BASICS

SUMMARY

1. Backup Routes via Fast Convergence / Dual
2. Simple Configuration
3. Flexibility in Summarization
4. Unequal Cost LB
5. Distance Vector and Link State combined with backup paths
6. Use its own Layer 4 protocol

EIGRP Tables and Definition

1. Neighbor Table - show ip eigrp neighbors - exchanging routes
2. Topology Table - have the successor (direct path) and feasible successor links
3. Routing Table - picking the best route / DUAL , will actively be used

Feasible Distance (FD)
1. Recived routing updates
2. Adverstice Distance + Link Cost (Metric)

Advertised Distance (AD)
1. How far from a device to another device (Metric COST)

Successor
1. Route with the lowest FD
2. Best and lowest
3. Primary route

Feasible Successor
1. Backup route
2. The AD must be lower than the FD of the successor

Active and Passive Routes
1. Active - Network Down
2. Passive - Network/Route is up

EIGRP Neighbor Relationship

1. Hello - forms relationship
2. Update - sends update
3. Query - ask about routes and backup
4. Reply - Response to query
5. Ack - Acknowledge update, query, and reply message

SIA - stuck in active route, removes the neighbor relationship

Metric Calculation

Bandwidth K
Delay K3 (consider as Static Value can be seen in show IP interface / hop counter)
Reliability K4 and K5 (Dynamic Value)
Load K2 (Dynamic Values)

Real Metric - 256 x (A:slowest bandwidth + B:delays of linsk)

BASE CONFIGURATION

ROUTER A
1. show ip interface brief
2. int s0/0
3. bandwidth 128
4. exit
5. int  s0/1
6. bandwidth 256
7. exit
8. router eigrp 10
9. no auto-summary
auto summary makes it class full
best practice to disable auto summary
10.1 network 192.0.0.0 0.0.0.255
10.2 network 192.0.0.1 0.0.0.0
        network 192.0.1.1 0.0.0.0
        network 192.0.2.1 0.0.0.0
10.3 network 192.0.0.0
10.4 network 0.0.0.0 255.255.255.255

show ip protocol
192.0.0.0
192.0.0.1/32
192.0.1.1/32
192.0.2.1/32
192.0.0.0/24
0.0.0.0
expected output of 10.1-4

ROUTER B
router eigp 10
network 10.1.0.0 0.0.0.255
no auto summary

ROUTER C
router eigrp 10
network 10.1.0.0 0.0.0.255
no auto summary

Show commands to check if eigrp is running

show ip eigrp neighbors
show ip eigrp interfaces

Routing Notes 04 GRE and DMVPN 2

GRE CONFIGURATION

ROUTER 1

conf t
interface tunnel 0
tunnel source 29.10.10.1
tunnel destination 29.10.10.2
ip address 192.168.1.1 255.255.255.0

ROUTER 2

conf t
interface tunnel 0
tunnel source 29.10.10.2
tunnel destination 29.10.10.1
ip address 192.168.1.2 255.255.255.0

ROUTER 1

router rip
no auto summary
network 192.168.1.0
network 29.0.0.0

ROUTER 2

router rip
no auto summary
network 192.168.1.0
network 29.0.0.0

DIFFERENCE BETWEEN GRE AND DMVPN

GRE - Generic Route Encapsulation
1. Runs on Multicast Traffic
2. VPN, routes are treated private on public connection
3. Ability to encapsulate private ip address to public connection

DMVPN - Next Hop Resolution Protocol

Routing Notes 03 GRE and DMVPN 1

DMVPN CONFIGURATION

ROUTER 1

conf t
interface tunnel 0
tunnel source s0/0
tunnel mode gre multipoint
enabling DMVPN
tunnel key 1234
security feature
ip nhrp network-id 10
encryption
ip nhrp authentication kahitano
security feature
ip nhrp map multicast dynamic
dynamically resolve next hop, connect directly together all devices
address 192.168.0.1 255.255.255.0
address of router 1
tunnel path-mtu-discovery
how big a packet can be send, prevent from defragmentation
ip mtu 1400
mtu size
ip tcp adjust-mss 1360
tcp size
no split horizon
prevent split horizon to enable RIP
show ip interface brief

ROUTER 2

conf t
interface tunnel 0
tunnel source s0/1
tunnel mode gre multipoint
tunnel key 1234
ip nhrp network-id 10
ip nhrp authentication kahitano
ip nhrp map multicast dynamic
ip nhrp nhs 192.168.0.1
ip nhrp map 192.192.168.0.1 29.10.1.2
ip nhrp map multicast 29.10.1.2
address 192.168.2. 255.255.255.0
ip mtu 1400
ip tcp adjust-mss 1360

ROUTER 3

conf t
interface tunnel 0
tunnel source s0/1
tunnel mode gre multipoint
tunnel key 1234
ip nhrp network-id 10
ip nhrp authentication kahitano
ip nhrp map multicast dynamic
ip nhrp nhs 192.168.0.1
ip nhrp map 192.192.168.0.1 29.10.1.2   address of router 2
ip nhrp map multicast 29.10.1.2
address 192.168.3. 255.255.255.0
ip mtu 1400
ip tcp adjust-mss 1360

DMVP TESTING

ROUTER 2

show ip nhrp
ping 192.168.0.1
ping 192.168.0.3
show ip nhrp

ENABLING ROUTING PROTOCOL

ROUTER 3

show ip nhrp
router rip
version 2
no auto
network 192.168.0.0
network 29.0.0.0

ROUTER 2

router rip
version 2
network 192.168.0.0
network 29.0.0.0
no auto

ROUTER 1

router rip
version 2
network 192.168.0.0
network 29.0.0.0
no auto

ROUTER 2

show ip route  look for RIP route on tunnel 0