11 December 2017

CCIE-Wireless lab prep - notas - LoadBalancing e IPv6



Etherchannel Load-Balancing

(config)#port-channel load-balance <tipo de lb>


(config)#port-channel load-balance ?

  dst-ip       Dst IP Addr

  dst-mac      Dst Mac Addr

  src-dst-ip   Src XOR Dst IP Addr

  src-dst-mac  Src XOR Dst Mac Addr

  src-ip       Src IP Addr

  src-mac      Src Mac Addr


Com WLCs é boa prática usar src-dst-ip

--------------------------------------------

IPV6
configurar ipv6 num interface

O mais básico e simples é deixar que os equipamentos configurem automaticamente:

(config-if)# ipv6 address autoconfig


é atribuído automaticamente um endereço baseado nos prefixos em Router Advertisement, em formato eui-64.

Em alternativa, é possível configurar os endereços de acordo com os seguintes comandos:



(config)#int <slot>/<port>
(config-if)#ipv6 add <ipv6 address> <type>
 
·         ipv6 address ipv6-prefix/prefix-length eui-64
·         ipv6 address ipv6-prefix/prefix-length link-local
·         ipv6 address ipv6-prefix/prefix-length anycast

Example:
Device(config-if)# ipv6 address 2001:DB8:0:1::/64 eui-64
·         Specifying the ipv6 address eui-64 command configures global IPv6 addresses with an interface identifier (ID) in the low-order 64 bits of the IPv6 address. Only the 64-bit network prefix for the address needs to be specified; the last 64 bits are automatically computed from the interface ID.

Example:
Device(config-if)# ipv6 address FE80::260:3EFF:FE11:6770 link-local
·         Specifying the ipv6 address link-local command configures a link-local address on the interface that is used instead of the link-local address that is automatically configured when IPv6 is enabled on the interface.

Example:
Device(config-if) ipv6 address 2001:DB8:1:1:FFFF:FFFF:FFFF:FFFE/64 anycast
·         Specifying the ipv6 address anycast command adds an IPv6 anycast address.
IPv6 Address Type: Anycast
An anycast address is an address that is assigned to a set of interfaces that typically belong to different nodes. A packet sent to an anycast address is delivered to the closest interface (as defined by the routing protocols in use) identified by the anycast address. Anycast addresses are syntactically indistinguishable from unicast addresses, because anycast addresses are allocated from the unicast address space. Assigning a unicast address to more than one interface makes a unicast address an anycast address. Nodes to which the anycast address is assigned must be explicitly configured to recognize that the address is an anycast address.

29 November 2017

CCIE-Wireless lab prep - back to basics - DTP, STP, Etherchannels



DTP (Dynamic Trunk Protocol) - Se porta estiver configurada com switchport mode dynamic DTP configura a porta como access ou trunk automaticamente. Não costuma ser problema porque configurar switchport mode access ou trunk evitam o DTP mas caso se pretenda desabilitar DTP numa porta fazer o comando “switchport nonnegociate”

Tagging da native VLAN!!!
(config)#vlan dot1q tag native

#sho vlan dot1q tag native


Spantree Protocol
default of 32768. “Quanto menos, melhor”

(config)#span vlan <vlan> priority <prio>
Configura a priority manualmente.

(config)#span vlan <vlan> root primary
Aplica automaticamente o comando “span vlan <vlan> prio <prio>” de modo a que o SW tenha prio menor da rede.

(config)#span vlan <vlan> root secondary
Aplica automaticamente o comando “span vlan <vlan> prio <prio>” de modo a que o SW tenha a segunda menor prior da rede.

(config)#int <slot>/<port>
(config-if)#spanning-tree vlan <vlan> cost <cost>
Aumenta o “custo” de interface

(config)#int <int>
(config-if)#span vlan <vlan> port-priority <prio>
Atribui prioridade a um interface específico.

(config)#span portfast bpduguard default
Bpduguard – configurado geralmente em portas access. Serve para impedir que um rogue switch lixe a spanning tree.

(config)#span portf bpdufilter default
Bpdufilter – retira a porta do spanning tree. Pode provocar loops porque o interface não tem STP para evitar loops

“Então e se o switch está no meio do monte e a porta ficar em errdisable? Tenho de lá ir?”
(config)#errdisable recovery cause <causa>
(config)#errdisable recovery cause bpduguard
(config)#errdisable recovery interval <seconds>


Etherchannel

Mode ON – etherchannel manual
LACP – open protocol
PAgP – protocol cisco

(config-if)#channel-group <po id> mode <mode>
(config-if)#channel-group <po id> mode <mode>
  active     Enable LACP unconditionally
  auto       Enable PAgP only if a PAgP device is detected
  desirable  Enable PAgP unconditionally
  on         Enable Etherchannel only
  passive    Enable LACP only if a LACP device is detected

Active
Passive
Ok
LACP
Active
Active
Ok
Passive
Passive
nope
Auto
Auto
nope
PAgP
Auto
Desirable
Ok
Desirable
Desirable
Ok
ON
ON
Ok
manual
ON
≠ ON
nope