Arquivo da categoria: cisco

Cisco Basic Commands list for beginners | Cisco command levels EXEC Modes – Lista básica de comandos para iniciantes em Cisco

Em desenvolvimento baseado no link http://commonerrors.blogspot.com.br/2015/08/cisco-basic-commands-for-beginners.html

Será uma copia mas comentando os show que não foram comentados em português

Cisco IOS command level and their Basic Commands:

Este artigo tem comandos básicos da Cisco, para mais comandos e detalhes, você pode visitar a Cisco.com

O que são os Cisco command levels EXEC Mode e como acessalos:

Com os níveis de comando da Cisco EXEC Mode, você pode controlar os privilégios do usuário. Esses controles de privilégio de usuário podem ser fornecidos por meio de senha. Existem três níveis de comando em todos os dispositivos Cisco IOS. Em cada nível de comando você tem privilégios e controle específicos. Estes comandos Level são como abaixo:

  •  User Mode
  • Privileged EXEC  Mode
  • Global configuration Mode

 

Cisco User Mode Cisco:

In user EXEC mode you can execute limited array of show commands, basic reachability tests, such as ping and traceroute, as well as other ways of viewing configurations and status info of a Cisco device without the ability to make changes. This command level is represented by symbol “>”, by using command you can “enable” you can go to next mode i.e. privileged EXEC mode.

Cisco Privileged EXEC Mode

Privileged EXEC mode is represented by symbol “#”.

This mode is for users that have been some admin privileges and need to make changes, but in this mode most of commands are related to view/show configurations and debugs.

In privileged EXEC Mode most of command show the status of cisco devices, module and startup, running configurations and configurations of different protocols.

Cisco Global Configuration Mode

This mode is for administrator and power user, from this mode you can configure your Cisco device can configure different Protocols. Some of common commands for configurations of this mode are as under.

You can access or go to global configuration mode by using command “configure terminal” when you are in Privileged EXEC mode.

R1>

R1>enable                                          Entering into Privileged EXEC Mode

R1#configure terminal                   Entering into Global Configuration Mode

R1(config)#

Note: In this article all Cisco commands are represented with purple color.

Example of Commands in Privileged EXEC Mode:

How to Check the IOS/hardware version of Cisco Device:

R1#Show Version 

Show version command will displays the configuration of the system hardware, the IOS version, and the names and sources of configuration files and the boot images. This command also displays information about how the system was last started and how long the router has been running since that start.

How to set Gateway on Cisco router

You can configure or set a default gateway following commands:

  •  ip default-network
  • ip default-gateway
  • ip route 0.0.0.0 0.0.0.0

How to set Gateway of last resort

How to check all running configurations of Cisco Device:

Show running-config

This command will show all the configuration which are configure on Cisco device. You view output of show running-config

How to check the vlan details on Cisco:

Show Vlan

Click here to see the Outputof show vlan

How to check detail of specific interfaces on Cisco:

Show interface <interface name>
Command Example: show interface f0/0 (this command will show the detail of interface fastEthernet 0/0)

View output of showinterface f0/0 

How to check syslog errors:

show logging

show logging command displays the state of syslog error and event logging, including host addresses, and whether console logging is enabled. View output of show logging

How to check running process on Cisco Device:

show Processes 
This command will displays information about the active processes.

How to check the memory used by running process on Cisco:

show Processes memory
This command will displays the amount of memory used. See output of Show processes memory.

How to check Routing table on Cisco Router/Switch:

show ip route

Above command will show all dynamic and static routes on Cisco Device. A output of show ip route.

show ip route OSPF

Command will show all OSPF routes.

show ip route RIP

Command will show all RIP routes.

Show ip route EIGRP

This command will show all EIGRP routes.

How to check all interfaces details:

show interfaces

This command displays statistics for the network interfaces. Output of this command include following details

  1.             UP/down state of interface
  2.             MAC Address

      iii.            IP address

  1.             MTU ,BW Delay, duplex type of interfaces
  2.             Queueing strategy
  3.             Packet send/received

Click here to see the Outputof show interfaces

How to check the status of all interfaces on Cisco:

Show ip interface Brief

This command will show you the IP addresses, interfaces status (up/down), protocol status (up/down), you can view output of Show ip interface Brief from here.

Check neighbors detail and routing information | Cisco CDP commands    

 show cdp interface   

  show cdp neighbors [Detail]   

  show cdp entry Router 

 Ip domain-Lookup nsap    

 Show hosts    

Some other Examples of show commands:

Following are some others show command which are self-explanatory you can try these command on your Cisco device and view their output.

Show clock

Show controllers

Show mac-address-table 

Show memory

Show privilege

Show protocols

Show startup-config

Show Flash 

Show spanning-tree

Examples of Global configuration Commands:

 To enter in Global configuration mode type: config terminal. Global configuration mode is often used to configure the network Commands.

Set hostname of Router:

Router(config)#hostname <distinguished name>

Command Example: Router (config)# hostname R1 (This command will set the router name to R1)

How to set banner message:

banner motd <banner start identification> banner message <banner end identification>

Command Example:

banner motd #Unauthorized access to this device is prohibited!#    

Above command with set the banner to “Unauthorized access to this device is prohibited”

How to set IP address to Cisco interface:

Router(config)#  Interface <port number >

Router(config-int)# ip address <ip address number>

IP address Command Example:

 Router(config)#interface f0/0

Router(config)# ip address 176.16.32.1 255.255.255.0

(This will set the IP address 176.16.32.1/24 to interface f0/0)

How to up/on the Cisco router interface:

Router(config)#interface f0/0

Router(config-int)# no shutdown 

(above command will change the status of interface fo/o to active/up/ON)

How to set the interface speed:

Interface console type the following commands for configuring interface speed.

switch(config-if)# speed{10|100|auto

R1(config)#interface f0/1

R1(config-if)#speed 100

Above commands will configure the speed of 100MBs to interface f0/1.

How to set enable password on Cisco:

Router(config)#  Enable Password <password>

Enable password Command Example:

 Router(config)# Enable Password Cisco

(This will Establishes a enable password to Cisco)

How to set Telnet password on Cisco:

Router(config)#line vty 0 4
Router(config-line)#login
Router(config-line)#password cisco

(Above command will create a Telnet password to Cisco)

Cisco IP routing Commands:

How to set the static routing:   

Router(config-router)#ip route [destination_network] [mask] [next-hop_address

Static route command example:

Router(config-router)#ip route 210.22.22.2 255.255.255.0 192.168.0.1

Above command will set a static route for network 210.22.22.0. See static routing on gns3.

How to set the default route on Cisco Router    

Router(config)#ip default-network< network number >

Command Example: ip default-network 192.168.1.1

How to configure dynamic routing with Rip on Cisco:

Router(config)#Router rip    

Router(config-router)#Network <Network ID> 

Router(config-router)#Network 192.168.1.0

See more for configuration command example of RIP in Cisco from here.

How to configure OSPF on Cisco:

Router(config)#Router ospf process ID

Router(config-router)#Network <Network ID> <mask> area <area ID>

Router(config)#Router ospf 1

Router(config-router)#network 10.0.0.0 0.0.0.255 area 0

Above command will advertise the network 10.0.0.0/24 in area 0.

OSPFconfiguration commands example.

How to configure access-list on Cisco:

Access-List <access number> {permit | deny}  <IP address to block>

for more details Access list in Cisco

Cisco Switching Commands:

How to crate Vlan on Cisco: 

switch(vlan)# vlan <vlan-num> name <vlan name>

 switch(vlan)# vlan 10 name marking

Above command will create vlan 10 with name marketing.

How to set access port: 

switch# configure teriminal 

switch( config)# interface fo/o

 switch(config-if)# switchport mode access 

How to assign vlan to interface in Cisco:

switch( config)# interface <interface name/number>

switch(config-if)# switchport access vlan <vlan-num> 

 Command Example:

switch( config)# interface  f0/0

switch(config-if)# switchport access vlan 10

Above command will add interface f0/0 to vlan 10.

See vlan Configuration Example.

 How to create trunk port: 

After selecting the interface mode type the following commad.

switch(config-if)# switchport mode trunk 

How to allow the specific Vlans on Trunk Port:

switch(config-if)# switchport trunk allowed vlan < vlan-list>

Cisco Daily used commands:

Cisco Connectivity Test Commands:

Ping host name / IP address

R1> ping 10.0.0.1

traceroutehostname / IP address of destination

R1# traceroute 192.168.1.1

How to go back to previous command level: (From Global Configuration to privileged EXEC or User  mode):

  1. You can use command “Exit” or “end” for exiting the current EXEC mode, but if you want to go back to privileged EXEC  Mode from any mode simple hit the “Ctrl+Z” from keyboard.

 

In this article I have combine some of common and basic commands, if you think that there are some basic/important commands are missing here then please comment & I will update it accordingly. Thank you for reading it.

Acelerando a população da FIB pós switchover

Dica legal do blog log https://ethernuno.wordpress.com/2016/01/08/ccnp-switch-300-115-part-1-8-chassis-virtualization-and-aggregation-technologies/

Dos tópicos de CCNP SWITCH que fala de stackwise, passa algumas maneiras de acelerar o roteamento em caso de switchover.

Switchover is the manual switch from one system to a redundant or standby computer server, system, or network upon the failure or abnormal termination of the previously active server, system, or network, or to perform system maintenance, such as installing patches, and upgrading software or hardware.

chassis-virtualization-and-aggregation-technologies

Dica

Nonstop Forwarding

Nonstop forwarding (NSF) is an interactive method that focuses on quickly rebuilding the Routing Information Base (RIB) table after a supervisor switchover. The RIB is used to generate the FIB table for CEF, which is downloaded to any switch modules or hardware that can perform Cisco Express Forwarding (CEF).

Instead of waiting on any configured Layer 3 routing protocols to converge and rebuild the FIB, a router can use NSF to get assistance from other NSF-aware neighbors. The neighbors then can provide routing information to the standby supervisor, allowing the routing tables to be assembled quickly. In short, the Cisco proprietary NSF functions must be built in to the routing protocols on both the router that will need assistance and
the router that will provide assistance.

NSF is supported by the BGP, EIGRP, OSPF, and IS-IS routing protocols. To configure NSF, you must add the following commands to any routing protocol configuration on the switch.

BGP

OSPF

EIGRP

IS-IS

 

 

Exploit para Switchs Cisco e como resolver

Fonte: https://gbhackers.com/cisco-switches/

Vulnerability Description in Cisco Switches

O que causa? Controle total do elemento.

Verificarse esta habilitado:

#sh vstack config

desabilitar

# conf t

#no vstack

Affected Cisco Switches

  • Catalyst 4500 Supervisor Engines
  • Catalyst 3850 Series
  • Catalyst 3750 Series
  • Catalyst 3650 Series
  • Catalyst 3560 Series
  • Catalyst 2960 Series
  • Catalyst 2975 Series
  • IE 2000
  • IE 3000
  • IE 3010
  • IE 4000
  • IE 4010
  • IE 5000
  • SM-ES2 SKUs
  • SM-ES3 SKUs
  • NME-16ES-1G-P
  • SM-X-ES3 SKUs

This Flaw has been fixed by Cisco and released the patch CVE : CVE-2018-0171

Vídeo exemplo da invasão

CCNA questão de trouble de drag and drop

Acho muito boa essas questões, porque em toda prova tem coisas inúteis para o dia dia e ccna não é diferente…se a finalidade é passar na prova  e não saber o conteúdo basta decorar 300 questões que já resolve, mas focando na questão abaixo ela é totalmente trouble e “cai na vida real”

Vamos lá!

  1. Serial up e protocolo up? tudo certo!!! ou seja porta operacional
  2. Serial está up mas o protocolo está down, como estamos falando de SERIAL basta um ajuste do protocolo que sua porta sobe, por default o serial vem com HDLC, tente encapsulation ppp ou encap ? e vá testando os protocolos que o protocolo ficando UP problema resolvido então estamos falando de? LAYER 2 PROBLEM, lembrando que você não tem que se preocupar com clock se for o cliente.
  3. Serial down e protocolo down, porta física fora e também o protocolo o que nós leva a um problema de camada 1 cabo/conector etc
  4. Serial está administrativamente down eo line is down, o administrador deu manualmente shutdown na porta resposta? port disabled

troubleh-drag-and-drop-1

 

troubleh-drag-and-drop-2