Análisis de una transacción DHCP

Fecha: 10 de septiembre del 2014 Clase: Exploration 4

Escenario

Este laboratorio analiza la secuencia de tráfico DHCP que menciona el capítulo 7 de Exploration 4.

También se representa una situación de conflicto de direcciónes IP y como lo resuelve el servidor,

en este caso, un router Cisco 1841.

De la currícula Exploration 4:

En la nueva versión de CCNA 2 R&S:

1.- Generando tráfico DHCP:

C:\Users\CIT>ipconfig /release

Configuración IP de Windows

Adaptador de Ethernet Conexión de área local:

Sufijo DNS específico para la conexión. . :

Puerta de enlace predeterminada . . . . . :

C:\Users\CIT>ipconfig /renew

Configuración IP de Windows

Adaptador de Ethernet Conexión de área local:

Sufijo DNS específico para la conexión. . :

Dirección IPv4. . . . . . . . . . . . . . . . . . . . . . . : 192.168.2.100

Máscara de subred . . . . . . . . . . . . . . . . . . : 255.255.255.0

Puerta de enlace predeterminada . . . . . : 192.168.2.1

C:\Users\CIT>

2.- Análisis del tráfico involucrado:

Frame 1: 342 bytes on wire (2736 bits), 342 bytes captured (2736 bits) on interface 0

Ethernet II, Src: 54:be:f7:57:f2:80 (54:be:f7:57:f2:80), Dst: 00:1f:9e:c2:7a:a2 (00:1f:9e:c2:7a:a2)

Internet Protocol Version 4, Src: 192.168.2.100 (192.168.2.100), Dst: 192.168.2.1 (192.168.2.1)

User Datagram Protocol, Src Port: 68 (68), Dst Port: 67 (67)

Bootstrap Protocol

Message type: Boot Request (1)

Hardware type: Ethernet (0x01)

Hardware address length: 6

Hops: 0

Transaction ID: 0x1137b344

Seconds elapsed: 3

Bootp flags: 0x0000 (Unicast)

Client IP address: 192.168.2.100 (192.168.2.100)

Your (client) IP address: 0.0.0.0 (0.0.0.0)

Next server IP address: 0.0.0.0 (0.0.0.0)

Relay agent IP address: 0.0.0.0 (0.0.0.0)

Client MAC address: 54:be:f7:57:f2:80 (54:be:f7:57:f2:80)

Client hardware address padding: 00000000000000000000

Server host name not given

Boot file name not given

Magic cookie: DHCP

Option: (53) DHCP Message Type

Length: 1

DHCP: Release (7)

Option: (54) DHCP Server Identifier

Length: 4

DHCP Server Identifier: 192.168.2.1 (192.168.2.1)

Option: (61) Client identifier

Length: 7

Hardware type: Ethernet (0x01)

Client MAC address: 54:be:f7:57:f2:80 (54:be:f7:57:f2:80)

Option: (255) End

Option End: 255

Padding

Frame 2: 342 bytes on wire (2736 bits), 342 bytes captured (2736 bits) on interface 0

Ethernet II, Src: 54:be:f7:57:f2:80 (54:be:f7:57:f2:80), Dst: ff:ff:ff:ff:ff:ff (ff:ff:ff:ff:ff:ff)

Internet Protocol Version 4, Src: 0.0.0.0 (0.0.0.0), Dst: 255.255.255.255 (255.255.255.255)

User Datagram Protocol, Src Port: 68 (68), Dst Port: 67 (67)

Bootstrap Protocol

Message type: Boot Request (1)

Hardware type: Ethernet (0x01)

Hardware address length: 6

Hops: 0

Transaction ID: 0x21f285ab

Seconds elapsed: 0

Bootp flags: 0x8000 (Broadcast)

Client IP address: 0.0.0.0 (0.0.0.0)

Your (client) IP address: 0.0.0.0 (0.0.0.0)

Next server IP address: 0.0.0.0 (0.0.0.0)

Relay agent IP address: 0.0.0.0 (0.0.0.0)

Client MAC address: 54:be:f7:57:f2:80 (54:be:f7:57:f2:80)

Client hardware address padding: 00000000000000000000

Server host name not given

Boot file name not given

Magic cookie: DHCP

Option: (53) DHCP Message Type

Length: 1

DHCP: Discover (1)

Option: (61) Client identifier

Length: 7

Hardware type: Ethernet (0x01)

Client MAC address: 54:be:f7:57:f2:80 (54:be:f7:57:f2:80)

Option: (50) Requested IP Address

Length: 4

Requested IP Address: 192.168.2.100 (192.168.2.100) (ver mas abajo tema de la registry)

Option: (12) Host Name

Length: 5

Host Name: CIT03

Option: (60) Vendor class identifier

Length: 8

Vendor class identifier: MSFT 5.0

Option: (55) Parameter Request List

Length: 12

Parameter Request List Item: (1) Subnet Mask

Parameter Request List Item: (15) Domain Name

Parameter Request List Item: (3) Router

Parameter Request List Item: (6) Domain Name Server

Parameter Request List Item: (44) NetBIOS over TCP/IP Name Server

Parameter Request List Item: (46) NetBIOS over TCP/IP Node Type

Parameter Request List Item: (47) NetBIOS over TCP/IP Scope

Parameter Request List Item: (31) Perform Router Discover

Parameter Request List Item: (33) Static Route

Parameter Request List Item: (121) Classless Static Route

Parameter Request List Item: (249) Private/Classless Static Route (Microsoft)

Parameter Request List Item: (43) Vendor-Specific Information

Option: (255) End

Option End: 255

Padding

Frame 3: 70 bytes on wire (560 bits), 70 bytes captured (560 bits) on interface 0

Ethernet II, Src: 00:1f:9e:c2:7a:a2 (00:1f:9e:c2:7a:a2), Dst: 54:be:f7:57:f2:80 (54:be:f7:57:f2:80)

Internet Protocol Version 4, Src: 192.168.2.1 (192.168.2.1), Dst: 192.168.2.100 (192.168.2.100)

Internet Control Message Protocol

Type: 8 (Echo (ping) request)(verificación de IP ya utilizada)

Code: 0

Checksum: 0xf11b [correct]

Identifier (BE): 8 (0x0008)

Identifier (LE): 2048 (0x0800)

Sequence number (BE): 1 (0x0001)

Sequence number (LE): 256 (0x0100)

Data (28 bytes)

0000 00 00 00 00 0a 6e 46 64 ab cd ab cd ab cd ab cd .....nFd........

0010 ab cd ab cd ab cd ab cd ab cd ab cd ............

Frame 4: 70 bytes on wire (560 bits), 70 bytes captured (560 bits) on interface 0

Ethernet II, Src: 00:1f:9e:c2:7a:a2 (00:1f:9e:c2:7a:a2), Dst: 54:be:f7:57:f2:80 (54:be:f7:57:f2:80)

Internet Protocol Version 4, Src: 192.168.2.1 (192.168.2.1), Dst: 192.168.2.100 (192.168.2.100)

Internet Control Message Protocol

Type: 8 (Echo (ping) request) (verificación de IP ya utilizada)

Code: 0

Checksum: 0xeb3e [correct]

Identifier (BE): 8 (0x0008)

Identifier (LE): 2048 (0x0800)

Sequence number (BE): 2 (0x0002)

Sequence number (LE): 512 (0x0200)

Data (28 bytes)

0000 00 00 00 00 0a 6e 4c 40 ab cd ab cd ab cd ab cd .....nL@........

0010 ab cd ab cd ab cd ab cd ab cd ab cd ............

Frame 5: 342 bytes on wire (2736 bits), 342 bytes captured (2736 bits) on interface 0

Ethernet II, Src: 00:1f:9e:c2:7a:a2 (00:1f:9e:c2:7a:a2), Dst: ff:ff:ff:ff:ff:ff (ff:ff:ff:ff:ff:ff)

Internet Protocol Version 4, Src: 192.168.2.1, Dst: 255.255.255.255(en ambas currículas aparece como unicast)

User Datagram Protocol, Src Port: 67 (67), Dst Port: 68 (68)

Bootstrap Protocol

Message type: Boot Reply (2)

Hardware type: Ethernet (0x01)

Hardware address length: 6

Hops: 0

Transaction ID: 0x21f285ab

Seconds elapsed: 0

Bootp flags: 0x8000 (Broadcast)

Client IP address: 0.0.0.0 (0.0.0.0)

Your (client) IP address: 192.168.2.100 (192.168.2.100)

Next server IP address: 0.0.0.0 (0.0.0.0)

Relay agent IP address: 0.0.0.0 (0.0.0.0)

Client MAC address: 54:be:f7:57:f2:80 (54:be:f7:57:f2:80)

Client hardware address padding: 00000000000000000000

Server host name not given

Boot file name not given

Magic cookie: DHCP

Option: (53) DHCP Message Type

Length: 1

DHCP: Offer (2) (en ambas currículas aparece como unicast)

Option: (54) DHCP Server Identifier

Length: 4

DHCP Server Identifier: 192.168.2.1 (192.168.2.1)

Option: (51) IP Address Lease Time

Length: 4

IP Address Lease Time: (86400s) 1 day (opción por default)

Option: (58) Renewal Time Value

Length: 4

Renewal Time Value: (43200s) 12 hours (al 50% de tiempo de alquiler)

Option: (59) Rebinding Time Value

Length: 4

Rebinding Time Value: (75600s) 21 hours (nuevo intento si el anterior fracasa)

Option: (1) Subnet Mask

Length: 4

Subnet Mask: 255.255.255.0 (255.255.255.0)

Option: (3) Router

Length: 4

Router: 192.168.2.1 (192.168.2.1)

Option: (255) End

Option End: 255

Padding

Frame 6: 348 bytes on wire (2784 bits), 348 bytes captured (2784 bits) on interface 0

Ethernet II, Src: 54:be:f7:57:f2:80 (54:be:f7:57:f2:80), Dst: ff:ff:ff:ff:ff:ff (ff:ff:ff:ff:ff:ff)

Internet Protocol Version 4, Src: 0.0.0.0 (0.0.0.0), Dst: 255.255.255.255 (255.255.255.255)

User Datagram Protocol, Src Port: 68 (68), Dst Port: 67 (67)

Bootstrap Protocol

Message type: Boot Request (1)

Hardware type: Ethernet (0x01)

Hardware address length: 6

Hops: 0

Transaction ID: 0x21f285ab

Seconds elapsed: 0

Bootp flags: 0x8000 (Broadcast)

Client IP address: 0.0.0.0 (0.0.0.0)

Your (client) IP address: 0.0.0.0 (0.0.0.0)

Next server IP address: 0.0.0.0 (0.0.0.0)

Relay agent IP address: 0.0.0.0 (0.0.0.0)

Client MAC address: 54:be:f7:57:f2:80 (54:be:f7:57:f2:80)

Client hardware address padding: 00000000000000000000

Server host name not given

Boot file name not given

Magic cookie: DHCP

Option: (53) DHCP Message Type

Length: 1

DHCP: Request (3)

Option: (61) Client identifier

Length: 7

Hardware type: Ethernet (0x01)

Client MAC address: 54:be:f7:57:f2:80 (54:be:f7:57:f2:80)

Option: (50) Requested IP Address

Length: 4

Requested IP Address: 192.168.2.100 (192.168.2.100)

Option: (54) DHCP Server Identifier

Length: 4

DHCP Server Identifier: 192.168.2.1 (192.168.2.1)

Option: (12) Host Name

Length: 5

Host Name: CIT03

Option: (81) Client Fully Qualified Domain Name

Length: 8

Flags: 0x00

0000 .... = Reserved flags: 0x00

.... 0... = Server DDNS: Some server updates

.... .0.. = Encoding: ASCII encoding

.... ..0. = Server overrides: No override

.... ...0 = Server: Client

A-RR result: 0

PTR-RR result: 0

Client name: CIT03

Option: (60) Vendor class identifier

Length: 8

Vendor class identifier: MSFT 5.0

Option: (55) Parameter Request List

Length: 12

Parameter Request List Item: (1) Subnet Mask

Parameter Request List Item: (15) Domain Name

Parameter Request List Item: (3) Router

Parameter Request List Item: (6) Domain Name Server

Parameter Request List Item: (44) NetBIOS over TCP/IP Name Server

Parameter Request List Item: (46) NetBIOS over TCP/IP Node Type

Parameter Request List Item: (47) NetBIOS over TCP/IP Scope

Parameter Request List Item: (31) Perform Router Discover

Parameter Request List Item: (33) Static Route

Parameter Request List Item: (121) Classless Static Route

Parameter Request List Item: (249) Private/Classless Static Route (Microsoft)

Parameter Request List Item: (43) Vendor-Specific Information

Option: (255) End

Option End: 255

Frame 7: 342 bytes on wire (2736 bits), 342 bytes captured (2736 bits) on interface 0

Ethernet II, Src: 00:1f:9e:c2:7a:a2 (00:1f:9e:c2:7a:a2), Dst: ff:ff:ff:ff:ff:ff (ff:ff:ff:ff:ff:ff)

Internet Protocol Version 4, Src: 192.168.2.1 (192.168.2.1), Dst: 255.255.255.255 (255.255.255.255)

User Datagram Protocol, Src Port: 67 (67), Dst Port: 68 (68)

Bootstrap Protocol

Message type: Boot Reply (2)

Hardware type: Ethernet (0x01)

Hardware address length: 6

Hops: 0

Transaction ID: 0x21f285ab

Seconds elapsed: 0

Bootp flags: 0x8000 (Broadcast)

Client IP address: 0.0.0.0 (0.0.0.0)

Your (client) IP address: 192.168.2.100 (192.168.2.100)

Next server IP address: 0.0.0.0 (0.0.0.0)

Relay agent IP address: 0.0.0.0 (0.0.0.0)

Client MAC address: 54:be:f7:57:f2:80 (54:be:f7:57:f2:80)

Client hardware address padding: 00000000000000000000

Server host name not given

Boot file name not given

Magic cookie: DHCP

Option: (53) DHCP Message Type

Length: 1

DHCP: ACK (5)

Option: (54) DHCP Server Identifier

Length: 4

DHCP Server Identifier: 192.168.2.1 (192.168.2.1)

Option: (51) IP Address Lease Time

Length: 4

IP Address Lease Time: (86400s) 1 day

Option: (58) Renewal Time Value

Length: 4

Renewal Time Value: (43200s) 12 hours

Option: (59) Rebinding Time Value

Length: 4

Rebinding Time Value: (75600s) 21 hours

Option: (1) Subnet Mask

Length: 4

Subnet Mask: 255.255.255.0 (255.255.255.0)

Option: (3) Router

Length: 4

Router: 192.168.2.1 (192.168.2.1)

Option: (255) End

Option End: 255

Padding

Frame 8: 342 bytes on wire (2736 bits), 342 bytes captured (2736 bits) on interface 0

Ethernet II, Src: 54:be:f7:57:f2:80 (54:be:f7:57:f2:80), Dst: ff:ff:ff:ff:ff:ff (ff:ff:ff:ff:ff:ff)

Internet Protocol Version 4, Src: 192.168.2.100 (192.168.2.100), Dst: 255.255.255.255 (255.255.255.255)

User Datagram Protocol, Src Port: 68 (68), Dst Port: 67 (67)

Bootstrap Protocol

Message type: Boot Request (1)

Hardware type: Ethernet (0x01)

Hardware address length: 6

Hops: 0

Transaction ID: 0xcd27cf54

Seconds elapsed: 0

Bootp flags: 0x8000 (Broadcast)

Client IP address: 192.168.2.100 (192.168.2.100)

Your (client) IP address: 0.0.0.0 (0.0.0.0)

Next server IP address: 0.0.0.0 (0.0.0.0)

Relay agent IP address: 0.0.0.0 (0.0.0.0)

Client MAC address: 54:be:f7:57:f2:80 (54:be:f7:57:f2:80)

Client hardware address padding: 00000000000000000000

Server host name not given

Boot file name not given

Magic cookie: DHCP

Option: (53) DHCP Message Type

Length: 1

DHCP: Inform (8) (informa a todos los posibles servidores de DHCP de la red)

Option: (61) Client identifier

Length: 7

Hardware type: Ethernet (0x01)

Client MAC address: 54:be:f7:57:f2:80 (54:be:f7:57:f2:80)

Option: (12) Host Name

Length: 5

Host Name: CIT03

Option: (60) Vendor class identifier

Length: 8

Vendor class identifier: MSFT 5.0

Option: (55) Parameter Request List

Length: 13

Parameter Request List Item: (1) Subnet Mask

Parameter Request List Item: (15) Domain Name

Parameter Request List Item: (3) Router

Parameter Request List Item: (6) Domain Name Server

Parameter Request List Item: (44) NetBIOS over TCP/IP Name Server

Parameter Request List Item: (46) NetBIOS over TCP/IP Node Type

Parameter Request List Item: (47) NetBIOS over TCP/IP Scope

Parameter Request List Item: (31) Perform Router Discover

Parameter Request List Item: (33) Static Route

Parameter Request List Item: (121) Classless Static Route

Parameter Request List Item: (249) Private/Classless Static Route (Microsoft)

Parameter Request List Item: (43) Vendor-Specific Information

Parameter Request List Item: (252) Private/Proxy autodiscovery

Option: (255) End

Option End: 255

Padding

Frame 9: 342 bytes on wire (2736 bits), 342 bytes captured (2736 bits) on interface 0

Ethernet II, Src: 00:1f:9e:c2:7a:a2 (00:1f:9e:c2:7a:a2), Dst: 54:be:f7:57:f2:80 (54:be:f7:57:f2:80)

Internet Protocol Version 4, Src: 192.168.2.1 (192.168.2.1), Dst: 192.168.2.100 (192.168.2.100)

User Datagram Protocol, Src Port: 67 (67), Dst Port: 68 (68)

Bootstrap Protocol

Message type: Boot Reply (2)

Hardware type: Ethernet (0x01)

Hardware address length: 6

Hops: 0

Transaction ID: 0xcd27cf54

Seconds elapsed: 0

Bootp flags: 0x8000 (Broadcast)

Client IP address: 192.168.2.100 (192.168.2.100)

Your (client) IP address: 0.0.0.0 (0.0.0.0)

Next server IP address: 0.0.0.0 (0.0.0.0)

Relay agent IP address: 0.0.0.0 (0.0.0.0)

Client MAC address: 54:be:f7:57:f2:80 (54:be:f7:57:f2:80)

Client hardware address padding: 00000000000000000000

Server host name not given

Boot file name not given

Magic cookie: DHCP

Option: (53) DHCP Message Type

Length: 1

DHCP: ACK (5) (da acuse de recuse de recibo del alquiler)

Option: (54) DHCP Server Identifier

Length: 4

DHCP Server Identifier: 192.168.2.1 (192.168.2.1)

Option: (1) Subnet Mask

Length: 4

Subnet Mask: 255.255.255.0 (255.255.255.0)

Option: (3) Router

Length: 4

Router: 192.168.2.1 (192.168.2.1)

Option: (255) End

Option End: 255

Padding

3.- Verificación en el router:

BsAs#sh ip dhcp bind

Bindings from all pools not associated with VRF:

IP address Client-ID/ Lease expiration Type

Hardware address/

User name

192.168.2.100 0154.bef7.57f2.80 Sep 11 2014 07:12 PM Automatic

BsAs#

Detalle:

The unique identification of the client is specified in dotted hexadecimal notation; for example, 0154.bef7.57f2.80,

where 01 represents the Ethernet media type. Fuente: http://www.cisco.com

BsAs#sh arp

Protocol Address Age (min) Hardware Addr Type Interface

Internet 10.0.0.5 134 001d.46a5.2761 ARPA FastEthernet0/1

Internet 10.0.0.6 - 001f.9ec2.7aa3 ARPA FastEthernet0/1

Internet 192.168.2.1 - 001f.9ec2.7aa2 ARPA FastEthernet0/0

Internet 192.168.2.100 9 54be.f757.f280 ARPA FastEthernet0/0 (sin el 01 del show anterior)

BsAs#

4.- Pruebas con la IP 192.168.2.100 utilizada como IP fija y solapada en el rango DHCP:

Se simula la situación donde se conecta a la red una PC con IP fija que se encuentra dentro

del rango de direcciones del pool DHCP, analizamos que sucede tras bambalinas.

En la PC con DHCP:

Las PCs con sistema operativo Windows solicitan una dirección DHCP, pero con preferencia

a la última IP utilizada, es información queda almacenada en la registry:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\Tcpip\Parameters\Interfaces\

Verificación de la preferencia de una IP (aún luego de realizado el ipconfig /release):

Al realizar ipconfig /renew:

C:\Users\CIT>ipconfig /renew

Configuración IP de Windows

Error al renovar la interfaz Conexión de área local : El cliente DHCP ha obtenido una dirección IP

que ya está en uso en la red. La interfaz local será deshabilitada hasta que el cliente DHCP pueda

obtener una nueva dirección.

C:\Users\CIT>ipconfig

Configuración IP de Windows

Adaptador de Ethernet Conexión de área local:

Sufijo DNS específico para la conexión. . :

Dirección IPv4. . . . . . . . . . . . . . . . . . . . . . .: 192.168.2.101

Máscara de subred . . . . . . . . . . . . . . . . . . : 255.255.255.0

Puerta de enlace predeterminada . . . . . : 192.168.2.1

C:\Users\CIT>ping 192.168.2.1 (verificamos conectividad)

Haciendo ping a 192.168.2.1 con 32 bytes de datos:

Respuesta desde 192.168.2.1: bytes=32 tiempo<1m TTL=255

Estadísticas de ping para 192.168.2.1:

Paquetes: enviados = 4, recibidos = 4, perdidos = 0

(0% perdidos),

Tiempos aproximados de ida y vuelta en milisegundos:

Mínimo = 0ms, Máximo = 0ms, Media = 0ms

C:\Users\CIT>

En la PC con IP fija:

En el router:

BsAs#clear ip dhcp binding * (borramos todas los alquileres)

BsAs#sh ip dhcp bind

Bindings from all pools not associated with VRF:

IP address Client-ID/ Lease expiration Type

Hardware address/

User name

BsAs#

Sep 13 09:06:56.259: DHCPD: Sending notification of DISCOVER:

Sep 13 09:06:56.259: DHCPD: htype 1 chaddr 54be.f757.f280

Sep 13 09:06:56.259: DHCPD: remote id 020a0000c0a8020100000000

Sep 13 09:06:56.259: DHCPD: circuit id 00000000

Sep 13 09:06:56.259: DHCPD: Seeing if there is an internally specified pool class:

Sep 13 09:06:56.259: DHCPD: htype 1 chaddr 54be.f757.f280

Sep 13 09:06:56.259: DHCPD: remote id 020a0000c0a8020100000000

Sep 13 09:06:56.259: DHCPD: circuit id 00000000

Sep 13 09:06:58.259: DHCPD: client requests 192.168.2.100. (esto es porque queda en la registry de Windows la última IP utilizada)

Sep 13 09:06:58.259: DHCPD: Adding binding to radix tree (192.168.2.100) (la IP que está utilizada por una PC con IP fija)

Sep 13 09:06:58.259: DHCPD: Adding binding to hash tree

Sep 13 09:06:58.259: DHCPD: assigned IP address 192.168.2.100 to client 0154.bef7.57f2.80.

Sep 13 09:06:58.259: DHCPD: Sending notification of ASSIGNMENT:

Sep 13 09:06:58.259: DHCPD: address 192.168.2.100 mask 255.255.255.0

Sep 13 09:06:58.259: DHCPD: htype 1 chaddr 54be.f757.f280

Sep 13 09:06:58.259: DHCPD: lease time remaining (secs) = 86400 (son 24 horas)

Sep 13 09:06:58.607: DHCPD: Sending notification of TERMINATION:

Sep 13 09:06:58.607: DHCPD: address 192.168.2.100 mask 255.255.255.0

Sep 13 09:06:58.607: DHCPD: reason flags: DECLINE

Sep 13 09:06:58.607: DHCPD: htype 1 chaddr 54be.f757.f280

Sep 13 09:06:58.607: DHCPD: lease time remaining (secs) = 86400

Sep 13 09:06:58.607: DHCPD: returned 192.168.2.100 to address pool DHCP.

Sep 13 09:06:58.607: %DHCPD-4-DECLINE_CONFLICT: DHCP address conflict: client 0154.bef7.57f2.80 declined 192.168.2.100.

Sep 13 09:07:08.611: DHCPD: Sending notification of DISCOVER:

Sep 13 09:07:08.611: DHCPD: htype 1 chaddr 54be.f757.f280

Sep 13 09:07:08.611: DHCPD: remote id 020a0000c0a8020100000000

Sep 13 09:07:08.611: DHCPD: circuit id 00000000

Sep 13 09:07:08.611: DHCPD: Seeing if there is an internally specified pool class:

Sep 13 09:07:08.611: DHCPD: htype 1 chaddr 54be.f757.f280

Sep 13 09:07:08.611: DHCPD: remote id 020a0000c0a8020100000000

Sep 13 09:07:08.611: DHCPD: circuit id 00000000

Sep 13 09:07:10.611: DHCPD: Adding binding to radix tree (192.168.2.101)

Sep 13 09:07:10.611: DHCPD: Adding binding to hash tree

Sep 13 09:07:10.611: DHCPD: assigned IP address 192.168.2.101 to client 0154.bef7.57f2.80.

Sep 13 09:07:10.611: DHCPD: Sending notification of ASSIGNMENT:

Sep 13 09:07:10.611: DHCPD: address 192.168.2.101 mask 255.255.255.0

Sep 13 09:07:10.611: DHCPD: htype 1 chaddr 54be.f757.f280

Sep 13 09:07:10.611: DHCPD: lease time remaining (secs) = 86400

BsAs#sh ip dhcp bind

Bindings from all pools not associated with VRF:

IP address Client-ID/ Lease expiration Type

Hardware address/

User name

192.168.2.101 0154.bef7.57f2.80 Sep 14 2014 09:07 AM Automatic

BsAs#

5.- Configuración del router:

BsAs#sh runn (sólo lo relevante)

version 12.4

hostname BsAs

ip dhcp pool DHCP

network 192.168.2.0 255.255.255.0

default-router 192.168.2.1

class RANGO

address range 192.168.2.100 192.168.2.150

ip dhcp class RANGO (esto acorta el pool de direcciones en lugar de utilizar toda la subred)

interface FastEthernet0/0

description LAN

ip address 192.168.2.1 255.255.255.0

duplex auto

speed auto

(2014) Burning minds with networking

Rosario, Argentina