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Cisco IOS Revision Commands

Show commands - Cisco routers

Show version - software version, config files, boot images, config register, basic config of router
Show ipx interface - status, ipx rip and sap received/sent, ipx access-lists
Show ipx route - ipx routing table
Show ipx servers - server list (name, port, hops, type of service)
Show ipx traffic - number/type of packets, RIP and SAP packets
Show protocol - ipx addresses of an interface, IP addresses and routing protocol
Show ip protocol - routing update times, networks active on, neighbour routers, administrative distances, AS number
Show access-lists - shows standard and extended access-lists on all interfaces
Show access-list 101
Show ip interface - IP addresses, masks, MTU, access-lists, split horizon, ICMP, CDP status, NAT statistics, LMI info, DLCIs
Show interface serial 0 - shows bandwidth, MTU, keepalives
Show ip route - ip routing table
Show cdp neighbor - deviceID, local intf, holdtime, capability, platform, remote portID
Show cdp entry * - IP address of neighbour, protocol info, platform, capability, portID, holdtime, same info as show version, neighbour device ID, local interface
Show cdp neighbor detail - same as above also IP address, version info
Show cdp traffic - info on traffic and errors
Show cdp interface - encapsulation, timer, holdtime for each intf
Show controllers serial 0 - shows DTE/DCE connections, buffer size, collisions, mac address
Show host(s) - shows hostname to IP resolution of hosts
Show session(s) - shows connections to a remote device
Show users - shows connections to your router, port and time connected
Show frame-relay lmi - lmi errors and lmi type
Show frame-relay pvc - all configured PVC's, DLCI numbers, status of connections, No. of BECN/FECN
Show frame-relay pvc 16
Show frame-relay map - ip to dlci mappings
Show run - display router config (RAM), configured PVCs, ACLs.

CCNA Cram sheet

Show commands - 1900 switch

Show mac-address-table
Show run
Show ip - like ipconfig
Show port system - shows switching method
Show vtp
Show trunk A allowed-vlans - shows which VLANS allowed on trunk link
Show vlan-membership
Show vlan 2
Show vlan - verify VLAN config
Show history - shows last 10 commands entered by default
Show terminal - shows terminal config + history buffer size

General router commands

Banner exec - for activation or incoming vty
Banner incoming - displayed on reverse telnet sessions
Banner login - displayed on all connected terminals. Displayed before MOTD banner but before login prompts
Bfe - manual emergency mode setting
Clear counters - clears counters on all interfaces
Clear frame-relay-inarp - clears dynamic mappings
Clear line 1 - clears vty 1 connection to a remote router
Clock set 10.30.10 28 may 2002
Config-register 0x2102 - changes config register
Copy flash tftp
Copy tftp flash - copies IOS image from tftp server default directory to router flash
Disable - to get back to user mode from privileged
Disconnect 1 - clears a connection to a remote router
Enable - to get into privileged mode
Enable last-resort - define enable action if no tacas servers respond
Enable use-tacas - tells the router to authenticate passwords through a tacas server
Encapsulation isl 3 - encapsulates ISL frame-tagging for VLAN 3 on an interface
Exec timeout 0 1 - sets console timeout to 1 second
Exec-timeout 0 0 - sets exec timeout to never timeout
Exec-timeout 1 0 - set exec timeout to 1 minute
Ip domain-lookup - enables DNS (use no form to stop this)
Ip domain-name nikmakris.com - appends domain name to hostname (required for DNS)
Ip host nik 172.17.1.63 - adds to host table (up to 8 ip addr)
Ip name-server - sets ip address(es) of DNS servers
Lock - locks the terminal
Logging synchronous - stops console messages overwriting commands
Logout - to logout of the router
Media-type 100BaseX - sets media type
Mrinfo - request neigbour and version information from a multicast router
No login - sets line, vty ports not to prompt for login info
Passive-inteface s0 - disables routing updates on interface (Global command) - they are not sent out this interface but they are still received.
Ping ipx 40.0000.0c8d.5c9d
Service password-encryption - encrypts passwords (Global command)
Terminal monitor - needed to view debug commands from telnet session
Terminal history size 50 - sets command history to 50 lines
Tftp-server system <image name> - Make router a tftp server

Configure commands

Interface Ethernet 2/0/1 - type slot / port adapter / port number (interface) for VIP cards
Config terminal - configures RAM
Config network (config net) - changes a config on a tftp host
Config memory - configure NVRAM
Ip address 172.17.1.63 255.255.255.0 secondary - adds a secondary subnet address to an interface
Clock rate 56000 - sets clock rate to 56kbps for DCE interfaces

Access Lists (ACL)

Access-enable - creates a temporary access-list entry
Access-template - creates a temporary access-list entry
Access-profile - apply user profile to interface

Access-list 1 permit 0.0.0.0 255.255.255.255 - same as next line
Access-list 1 permit any - permits any host
Access-list 1 permit 172.30.16.29 0.0.0.0 - same as next line
Access-list 1 permit host 172.30.16.29 - permits host 172.30.16.29
No access list 1 - deletes access list 1
Ip access-group 1 out (out is default)
Access-list 101 deny tcp 172.16.4.0 0.0.0.255 any eq telnet
Access-list 101 permit ip any any established (TCP connection)
Router(Config)#ip access-list standard nik
Router(Config std-nacl)#deny any log (log - logs packets)

No ip access-group in - won't delete inbound lists if you leave the in off the end of the command

Frame relay

Router(Config)#int s0
Router(Config-if)#encapsulation frame-relay cisco (default)
Router(Config-if)#exit
Router(Config)#int s0.16 point-to-point
Router(Config-if)#no inverse-arp
Router(Config-if)#ip address 172.17.1.63 255.255.255.0
Router(Config-if)#bandwidth 64 - sets bandwidth to 64kbps (Only used by routing protocols)
Router(Config-if)#frame-relay map ip 172.16.30.17 16 ietf broadcast - broadcast tells the router to send broadcasts out this intf

IGRP Configuration

Router(Config)#router igrp 50
Router(Config-router)#timers basic 15 45 0 60
Router(Config-router)#variance 1-128 (controls load balancing between best and worse metrics)
Router(Config-router)#traffic-share balanced/min
    Balanced - share inversely proportional to metrics
    Min - use routers that have only min costs
Router(Config-router)#network 128.6.0.0
Router(Config-router)#no metric holddown
Router(Config-router)#metric maximum-hop 50

IPX RIP Configuration

Router(Config)#ipx routing - enables IPX routing, RIP and SAP
Router(Config)#ipx maximum-paths 2 - enables equal cost load balancing over 2 paths
Router(Config)#ipx per-host-load-share - ensures all packets to 1 destination are sent over same line
Router(Config)#int e0
Router(Config-if)#ipx network 10 encapsulation sap secondary - assigns ipx network 10 to a secondary interface on Ethernet 0 with encapsulation Ethernet_802.2
Router(Config-if)#ipx delay 6 - sets tick metric for IPX RIP (LAN = 1, WAN = 6 default)
Router(Config-if)#exit

Cisco ISDN Configuration

Router(Config)#interface bri 0
Router(Config-if)#ip address 172.17.1.63 255.255.255.0
Router(Config-if)#no shutdown
Router(Config-if)#dialer-group 1
Router(Config-if)#dialer map ip 172.16.60.2 name 8042 8350661
(Next router ip - hostname of next route (auth) - number to dial)
Router(Config-if)#dialer load-threshold 2 either - makes both interfaces come up immediately
Router(Config-if)#dialer load-threshold 255 either - only brings up 2nd B-channel if first is 100% loaded
Router(Config-if)#hold-queue 75 in - holds 75 packets in the queue during connection
Router(Config-if)#dialer idle-timeout 300 - sets idle time out (120 default)
Router(Config-if)#encapsulation ppp
Router(Config-if)#exit
Router(Config)#dialer-list 1 list 110
Router(Config)#access-list 110 permit tcp any any eq smtp
Router(Config)#access-list 110 permit tcp any any eq telnet

Static/default routes

Ip route 0.0.0.0 0.0.0.0 172.16.20.1 = default route
Ip default-network 172.16.1.0
Ip route 172.17.1.63 255.255.255.0 serial 1 1 permanent - keeps static route even if router cannot communicate with it, administration distance 1

Cisco Discovery Protocol (CDP) commands

Cdp timer 90
Cdp holdtime 240
Cdp enable (no cdp enable)

1900 Switch Configuration

#config t
(Config)#enable password level 1 nikolas - usermode password
(Config)#enable password level 15 makris - enable password
(Config)#enable secret nik2 - precedes the enable p/w
(Config)#hostname nik
(Config)#vtp pruning enable - enables pruning on whole switch
(Config)#delete vtp - deletes VTP database
(Config)#vtp server (client/transparent)
(Config)#vtp domain nikolas
(Config)#vtp password cisco
(Config)#ip address 172.17.1.63 255.255.255.0
(Config)#ip default-gateway 172.17.1.50
(Config)#switching-mode store-and-forward (fragment-free)
(Config)#vlan 2 name sales
(Config)#vlan 3 name marketing
(Config)#int Ethernet 0/1 - slot 0/port 1
(Config-if)#vlan-membership static 2
(Config-if)#description Finance_VLAN
(Config-if)#port secure max-mac-count 1 - allows only one mac address per port
(Config-if)#exit
(Config)#int f0/26
(Config-if)#trunk on - enables trunking of all VLANS not just VLAN 1
(Config-if)#no trunk-vlan 3 - stops trunking vlan 3
(Config-if)#duplex full - sets to full duplex (auto sense default)
(Config-if)#exit
(Config)#copy tftp://192.168.0.120/cat1900EN_9_00.bin opcode - download into flash memory
(Config)#copy nvram tftp://192.168.0.120/cat1900EN
(Config)#copy tftp://192.168.0.120/cat1900EN nvram
(Config)#delete nvram - deletes config
(Config)#delete vtp - deletes VTP database
(Config)#clear mac-address-table [dynamic]

Cisco Debug commands

Debug ipx routing activity - info on RIP updates
Debug ipx sap - info on sap updates
Debug ip igrp events - what's being rec'd sent, route type (int/ext,system), source, dest
Debug ip igrp transactions - shows contents of routing updates
Debug ip rip - source/contents of updates, network, metrics
Debug frame-relay lmi - enables verification of connection
Debug ppp authentication
UNDEBUG ALL

Next set of revision notes: Layer 2 switching revision notes