Switch de acesso com tempo de resposta elevado

[Luizhen]

O nosso switch está com o tempo de resposta muito alto, creio que seja por causa da inundação de DHCP, ele fica gerando log diversos logs em pouquíssimos segundos, como este abaixo:

iaddr: 0.0.0.0, DHCP yiaddr: 0.0.0.0, DHCP siaddr: 0.0.0.0, DHCP giaddr: 0.0.0.0, DHCP chaddr: 0ee4.3cb5.5fdd
Aug 1 14:34:51: DHCP_SNOOPING: message type : DHCPDISCOVER DHCP ciaddr: 0.0.0.0, DHCP yiaddr: 0.0.0.0, DHCP siaddr: 0.0.0.0, DHCP giaddr: 0.0.0.0, DHCP chaddr: 0ee4.3cb5.5fdd
Aug 1 14:34:51: DHCP_SNOOPING_SW: bridge packet get invalid mat entry: FFFF.FFFF.FFFF, packet is flooded to ingress VLAN: (60)
Aug 1 14:34:51: DHCPSNOOP(hlfm_set_if_input): Setting if_input to Gi0/10 for pak. Was not set
Aug 1 14:34:51: DHCPSNOOP(hlfm_set_if_input): Clearing if_input for pak. Was Gi0/10
Aug 1 14:34:51: DHCPSNOOP(hlfm_set_if_input): Setting if_input to Gi0/10 for pak. Was not set
Aug 1 14:34:51: DHCP_SNOOPING: received new DHCP packet from input interface (GigabitEthernet0/10)
Aug 1 14:34:51: DHCP_SNOOPING: process new DHCP packet, message type: DHCPREQUEST, input interface: Gi0/10, MAC da: ffff.ffff.ffff, MAC sa: 0ee4.3cb5.5fdd, IP da: 255.255.255.255, IP sa: 0.0.0.0, DHCP ciaddr: 0.0.0.0, DHCP yiaddr: 0.0.0.0, DHCP siaddr: 0.0.0.0, DHCP giaddr: 0.0.0.0, DHCP chaddr: 0ee4.3cb5.5fdd
Aug 1 14:34:51: DHCP_SNOOPING: message type : DHCPREQUEST DHCP ciaddr: 0.0.0.0, DHCP yiaddr: 0.0.0.0, DHCP siaddr: 0.0.0.0, DHCP giaddr: 0.0.0.0, DHCP chaddr: 0ee4.3cb5.5fdd
Aug 1 14:34:51: DHCP_SNOOPING_SW: bridge packet get invalid mat entry: FFFF.FFFF.FFFF, packet is flooded to ingress VLAN: (60)
Aug 1 14:34:54: DHCPSNOOP(hlfm_set_if_input): Setting if_input to Gi0/10 for pak. Was not set
Aug 1 14:34:54: DHCPSNOOP(hlfm_set_if_input): Clearing if_input for pak. Was Gi0/10
Aug 1 14:34:54: DHCPSNOOP(hlfm_set_if_input): Setting if_input to Gi0/10 for pak. Was not set
Aug 1 14:34:54: DHCP_SNOOPING: received new DHCP packet from input interface (GigabitEthernet0/10)
Aug 1 14:34:54: DHCP_SNOOPING: process new DHCP packet, message type: DHCPREQUEST, input interface: Gi0/10, MAC da: ffff.ffff.ffff, MAC sa: d08e.79e0.18bd, IP da: 255.255.255.255, IP sa: 0.0.0.0, DHCP ciaddr: 0.0.0.0, DHCP yiaddr: 0.0.0.0, DHCP siaddr: 0.0.0.0, DHCP giaddr: 0.0.0.0, DHCP chaddr: d08e.79e0.18bd
Aug 1 14:34:54: DHCP_SNOOPING: message type : DHCPREQUEST DHCP ciaddr: 0.0.0.0, DHCP yiaddr: 0.0.0.0, DHCP siaddr: 0.0.0.0, DHCP giaddr: 0.0.0.0, DHCP chaddr: d08e.79e0.18bd
Aug 1 14:34:54: DHCP_SNOOPING_SW: bridge packet get invalid mat entry: FFFF.FFFF.FFFF, packet is flooded to ingress VLAN: (10)
Aug 1 14:34:55: DHCPSNOOP(hlfm_set_if_input): Setting if_input to Gi0/10 for pak. Was not set
Aug 1 14:34:55: DHCPSNOOP(hlfm_set_if_input): Clearing if_input for pak. Was Gi0/10
Aug 1 14:34:55: DHCPSNOOP(hlfm_set_if_input): Setting if_input to Gi0/10 for pak. Was not set
Aug 1 14:34:55: DHCP_SNOOPING: received new DHCP packet from input interface (GigabitEthernet0/10)
Aug 1 14:34:55: DHCP_SNOOPING: process new DHCP packet, message type: DHCPREQUEST, input interface: Gi0/10, MAC da: ffff.ffff.ffff, MAC sa: d08e.79e0.18bd, IP da: 255.255.255.255, IP sa: 0.0.0.0, DHCP ciaddr: 0.0.0.0, DHCP yiaddr: 0.0.0.0, DHCP siaddr: 0.0.0.0, DHCP giaddr: 0.0.0.0, DHCP chaddr: d08e.79e0.18bd
Aug 1 14:34:55: DHCP_SNOOPING: message type : DHCPREQUEST DHCP ciaddr: 0.0.0.0, DHCP yiaddr: 0.0.0.0, DHCP siaddr: 0.0.0.0, DHCP giaddr: 0.0.0.0, DHCP chaddr: d08e.79e0.18bd
Aug 1 14:34:55: DHCP_SNOOPING_SW: bridge packet get invalid mat entry: FFFF.FFFF.FFFF, packet is flooded to ingress VLAN: (10)

O que podemos fazer?

[SamuelGLN]

Olá @Luizhen!

Caso a interface Gi0/10 esteja em trunk, ela está com ip dhcp snooping trust configurado? Portas de upstream para os servidores DHCP devem conter essa configuração.

Se não for esse o caso, poderia compartilhar em qual versão está o SW?

Best regards
******* If This Helps, Please Rate *******

[Luizhen]

Samuel, boa tarde!

Sim, é uma porta trunk e o switch é o: Modelo: WS-C2960CX-8PC-L Versão: 15.2(7)E7  Imagem: C2960CX-UNIVERSALK9-M

Segue configuração da porta:

interface GigabitEthernet0/10
description ## UL-35 ##
switchport trunk allowed vlan 5,6,10,44,50,52-54,60,70,90,110,120,130,301,1000
switchport trunk allowed vlan add 1010
switchport mode trunk
switchport nonegotiate
logging event trunk-status
load-interval 30
spanning-tree link-type point-to-point
ip dhcp snooping trust

[Flavio Miranda]

Olá @Luizhen 

 Como está o uso de CPU e memória do switch?

show  proc cpu

[Luizhen]

Flávio, boa tarde!

Segue o uso completo em txt., o resumo abaixo:

SW_CTJL_38#show proc cpu
CPU utilization for five seconds: 18%/0%; one minute: 18%; five minutes: 19%

[MHM Cisco World]

no ip dhcp snooping information option

this need only 

MHM

[Luizhen]

I did this, but the logs keep appearing.

[MHM Cisco World]

You add it in Which SW?

I think you have one Access SW abd other core SW 

Ypu need to add it in access SW

When you config dhcp snooping 

MHM

[Luizhen]

I add it to the "Conf t" of switch 38 (which is the switch where the logs are being generated).

SW_CTJL_38#conf t
Enter configuration commands, one per line. End with CNTL/Z.
SW_CTJL_38(config)#
SW_CTJL_38(config)#no ip dhcp snooping information option

[MHM Cisco World]

Host connect to this SW or other SW?

You need to add it to SW host connect to and config with dhcp snooping 

MHM

[Luizhen]

The switch 38 is connected to switch 35, with the DHCP SNOOPING configuration on both.

[MHM Cisco World]

no ip dhcp snooping information option <<- need to add to SW35 if host connect to this SW

[Luizhen]

Yes, i make this, but not resolved:

SW_CTJL_35#conf t
Enter configuration commands, one per line. End with CNTL/Z.
SW_CTJL_35(config)#no ip dhcp snooping information option
SW_CTJL_35(config)#
SW_CTJL_35#

SW_CTJL_38# conf t
Enter configuration commands, one per line. End with CNTL/Z.
SW_CTJL_38(config)#no ip dhcp snooping information option
SW_CTJL_38(config)#exi

[MHM Cisco World]

The link interconnect both SW is config as trust or non trust?

MHM

[Luizhen]

Trust:

SW_CTJL_38#sh run int g0/10
Building configuration...

Current configuration : 339 bytes
!
interface GigabitEthernet0/10
description ## UL-35 ##
switchport trunk allowed vlan 5,6,10,44,50,52-54,60,70,90,110,120,130,301,1000
switchport trunk allowed vlan add 1010
switchport mode trunk
switchport nonegotiate
logging event trunk-status
load-interval 30
spanning-tree link-type point-to-point
ip dhcp snooping trust

SW_CTJL_35#sh run int g1/0/24
Building configuration...

Current configuration : 279 bytes
!
interface GigabitEthernet1/0/24
description ## DL-38 ##
switchport trunk allowed vlan 5,6,10,60,110,120,130,1010
switchport mode trunk
switchport nonegotiate
logging event trunk-status
load-interval 30
spanning-tree link-type point-to-point
ip dhcp snooping trust