Advanced Cisco Routing Study Guide

Advanced Cisco Routing Study Guide Advanced Cisco Routing Study Guide ............................................................................... 1 Managing Traffic and Access ......................................................................................... 1 Managing IP Traffic .................................................................................................... 1 Managing IPX/SPX Traffic ........................................................................................ 2 Configuring Queuing to Manage Traffic .................................................................... 3 Verifying ..................................................................................................................... 5 Configuring Scalable Routing Protocols ........................................................................ 5 VLSMs........................................................................................................................ 5 OSPF in a Single Area ................................................................................................ 5 Interconnecting OSPF Areas....................................................................................... 6 EIGRP ......................................................................................................................... 7 Optimizing Routing Update Operation....................................................................... 8 BGP ............................................................................................................................. 9 Dialup.............................................................................................................................. 9 Dial-on-Demand Routing............................................................................................ 9 Customizing DDR..................................................................................................... 10 Bridging ........................................................................................................................ 11 Transparent Bridge Configuration............................................................................ 11 Integrated Routing and Bridging .............................................................................. 11 Source-Route Bridging ............................................................................................. 12 Post Mortem.................................................................................................................. 12 Misc Notes ................................................................................................................ 13

Managing Traffic and Access Ways to Manage traffic: • • • • •

Filtering User & application traffic Filtering Broadcast traffic Adjusting Timers and periodic announcements Providing Static Entries in Tables Prioritizing Traffic

Managing IP Traffic Type of Access List

Range

IP standard IP extended

1-99 100-199

Bridge type-code IPX standard

200-299 800-899

1

IPX extended IPX SAP

900-999 1000-1099

NLSP route aggregation

1200-1299

access-list access-list-number {permit|deny} source [source-wildcard] any ip access-group access-list-number {in|out} for applying access list to a vty: access-class access-list-number {int|out} show access-list show ip access-list [access-list-number] clear access-list counters [access-list-number] show line ip helper-address address ip forward-protocol {udp [port] | nd | sdns} extended access list: access-list access-list-number {permit|deny} {protocol|protocol-keyword} {source source-wildcard | any} {destination destination-wildcard |any} [protocol-specificoptions] [log]

Managing IPX/SPX Traffic •

Filtering SAP traffic

ipx sap-interval interval The SAP interval defaults to 60 seconds. ipx input-sap-filter access-list-number ipx output-sap-filter access-list-number ipx router-sap-filter access-list-number SAP Service numbers

2

4 7

File Server Print Server

47 107

Advertising Print Server RCONSOLE

278

NDS Server •

Filtering RIP Traffic

ipx input-network-filter access-list-number •

Get Nearest Server (GNS Operation)

ipx gns-reply-disable ipx gns-response-delay ipx gns-round-robin ipx output-gns-filter •

Static SAP

ipx sap service-type name network.node socket hop-count ex: ipx sap 107 MAILSERV 160.0000.0C01.2B72 8104 1 ipx sap 4 FILESERV 165.0000.0C01.3B16 451 1 •

Verifying IPX Operation

show ipx interface show ipx route show ipx cache show ipx servers - this displays the router's SAP table show ipx traffic

Configuring Queuing to Manage Traffic

3

•

Weighted Fair Queuing

Breaks up "packet trains" and gives priority to low-volume traffic, like telnet. fair-queue 128 (128 is the discard threshold) New messages will not be queued until its conversation drops below 25% of the threshold. •

Priority Queuing

priority-list 1 protocol ip high tcp 23 priority-list 1 protocol appletalk medium priority-list 1 protocol ipx medium priority-list 1 protocol ip normal priority-list 1 default low ! interface serial 0 priority-group 1

priority-list list-number interface interface-type interface-number {high|medium|normal|low} •

Custom Queuing

queue-list list-number protocol protocol-name queue-number queue-keyword keywordvalue queue-list list-number interface interface-type interface-number queue-number queue-list list-number default queue-number Example: queue-list 1 interface E0 1 queue-list 1 protocol ip 2

4

queue-list 1 protocol ipx 3 queue-list 1 protocol appletalk 4 queue-list 1 default 5 ! interface serial 0 custom-queue-list 1

Verifying Router# show queuing The show interfaces command shows the queuing for each interface.

Configuring Scalable Routing Protocols VLSMs Know how route summarization works.

OSPF in a Single Area Hello packets are exchanged every 10 seconds. If a router is silent for 40 seconds, its neighbors believe it is down. When a router boots, it enters the init state. When two routers exchange packets, they enter the two-way state. After the DR and BDR are elected, the routers enter the Exstart State. They are ready to discover the link-state information about the internetwork. Then the master and slave routers exchange database description packets. This is the Exchange State. After routers are synchronized, they enter the Full State. router(config)#router ospf process-id router(config-router)#network address wildcard-mask area area-id router(config-if)#ip ospf priority number (from 0 to 255) router(config-if)#ip ospf cost cost Verifying OSPF operation:

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show ip protocol show ip route show ip ospf interface show ip ospf show ip ospf neighbor detail show ip ospf database debug ip ospf adj debug ip ospf events debug ip ospf flood debug ip ospf lsa-generation debug ip ospf packet debug ip ospf retransmission debug ip ospf spf debug ip ospf tree

Interconnecting OSPF Areas Know the difference between stubby, totally stubby and not so stubby areas, and how to identify each by looking at the routing table. LSA Type

Name

Description

1

Router link entry Network link entry Summary link entry

Generated by each router for each area for which it belongs

2 3 or 4

Generated by the designated driver in multiaccess networks Originated by ABRs. Describes the links between the ABR and the internal routers of a local area.

router(config-router)#area area-id stub [no-summary] Virtual links 6

router(config-router)#area area-id virtual-link router-id Verifying: show ip ospf border-routers show ip ospf virtual-links show ip ospf process-id show ip ospf database show ip ospf [process-id area-id] database [network] show ip ospf [process-id area-id] database [summary] show ip ospf [process-id area-id] database [asbr-summary] show ip ospf [process-id area-id] database [external] show ip ospf [process-id area-id] database [database-summary]

EIGRP show ip eirgrp neighbors EIGRP uses 5 metrics: Bandwidth, Delay, Reliability, Loading, and MTU. router(config)#router eigrp autonomous-system-number router(config-router)#network network-number router(config-if)#ipx sap-incremental eigrp autonomous-system-number [rsup-only] rsup-only is for using RIP instead of EIGRP to carry routing updates. router(config-if)#ip summary-address eigrp as-number address mask show ip eigrp neighbors show ip eigrp topology show ip route eigrp show ip protocols

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show ip eigrp traffic show ipx route show ipx eigrp neighbors show ipx eigrp togology

Optimizing Routing Update Operation router(config-router)#passive-interface type number router(config)#ip default-network network-number router(config)#ipx advertised-default-route-only network Route Filters: router(config-router)#distribute-list access-list-number | name out [interface-name | routing-process | autonomous-system-number] router(config-router)#distribute-list {access-list-number | name} in [type number] Administrative Distances Route Source

Default Distance

Connected Static

0 1

EIGRP Summary External BGP Internal EIGRP

5 20 90

IGRP OSPF

100 110

IS-IS RIP EGP

115 120 140

External EIGRP Internal BGP

170 200

Unknown

255

8

router(config-router)#redistribute protocol [process-id] [metric metric-value] [metrictype type-value] [subnets]

BGP router bgp 100 network 19.0.0.0 neighbor 15.1.1.2 remote-as 200 Verifying: show ip bgp show ip bgp paths show ip bgp summary show ip bgp neighbors

Dialup HDLC is the Cisco default encapsulation type on point-to-point links.

Dial-on-Demand Routing ISDN Standards • • •

E-Series protocols - Protocols that recommend telephone network standards for ISDN. I-Series protocols - deal with concepts, terminology, and general methods. Q-Serices protocols - cover how switching and signaling should operate. Particularly, know Q.921 and Q.931.

ISDN Switch types •

United States & Canada AT&T 5ess and 4ess; Nortel DMS-100

router(config)#dialer-list dialer-group protocol protocol-name [permit|deny|list] accesslist-number router(config-if)#dialer-group group-number example:

9

isdn switch-type basic-5ess ! Interface BRI0 ip address 10.1.0.1 255.255.255.0 encapsulation ppp dialer idle-timeout 180 dialer map ip 10.1.0.2 name p1r3 5551000 dialer-group 1 no fair-queue ppp authentication chap ! router rip network 10.0.0.0 ! no ip classless ip route 10.1.0.0 255.255.0.0 BRI0 dialer-list 1 protocol ip permit also: dialer load-threshold load [outbound | inbound | either]

Customizing DDR router(config-if)#backup interface interface-name router(config-if)#backup delay {enable-delay | never} {disable-delay | never} router(config-if)#backup load {enable-threshold | never} {disable-load | never} ppp multilink verifying: show dialer debug ppp multilink Snapshot routing: router(config-if)#snapshot client active-time quiet-time [suppress-statechange-updates] dialer router(config-if)#dialer map snapshot sequence-number name name dial-string router(config-if)#snapshot server active-timer [dialer]

10

Verifying: show snapshot clear snapshot quiet-time debug snapshot IPX Spoofing ipx spx-spoof ipx spx-idle-time ipx watchdog-spoof

Bridging Spamming Tree Protocols • •

DEC IEEE

Transparent Bridge Configuration router(config)#bridge bridge-group protocol {dec|ieee} router(config-if)#bridge-group bridge-group router(config)#bridge bridge-group priority number to set bridge root number is 0-255 for DEC and 0-64000 for IEEE with 128 and 32768 the defaults router(config-if)#bridge-group bridge-group path-cost cost

Integrated Routing and Bridging Bridge-Group Virtual Interface (BVI) handles IRB. interface BVI 20 ip address 10.1.0.1 255.255.0.0

11

! bridge irb bridge 20 protocol ieee bridge 20 route ip bridge 20 bridge appletalk

Source-Route Bridging router(config-if)#source-bridge local-ring bridge-number target-ring router(config-if)#source-bridge spanning for a virtual ring: source-bridge ring-group ring-number multiring ip enables the collection of RIF information for IP RIFs. SR/TRB source-bridge transparent ring-group pseudo-ring bridge-number tb-group [oui] Monitoring show source-bridge show rif show interfaces tokenring

Post Mortem know all show commands related to scalable routing protocols show eigrp neighbors for example don't worry much about bridging - three questions. One question was on Source route transparent bridiging Know dialup Know how Route Summarization works. For a route 174.10.25.0/20 What networks can be summarized?

12

174.10.15.0/24 174.10.17.0/24 174.10.31.0/24 174.10.32.0/24 pick 2 Know ospf stubby and totally stubby areas. Know how to set a gateway of last resort Know all of the OSPF codes in the show ip route command. Know eigrp. Private networks. Pick two. Filter internal router interfaces so private ip addresses don't leak out Filter external router interfaces so private ip addresses don't leak out Filter internal router interfaces so routing information doesn't leak in Filter internal router interfaces so routing information doesn't leak out

Misc Notes know all of the debug commands relating to routing and bridging. What is the default Cisco serial protocol? HDLC? debug rif

13