VNX for file network debugging tips--vlan Error

Failure phenomenon:

VLAN is a kind of virtual local area network, through VLAN can make the physical location in different network segment of the device group, can communicate as on the same network segment. This ensures that the reply packet always has the same VLAN ID tag as the incoming request packet. Packets that are passed in a VLAN are always outgoing from that VLAN. If the incoming request arrives without a token, the outbound reply is sent without a token. This article describes how to troubleshoot a VLAN.

Solution:

VLAN technology is supported on VNX, and if multiple logical interfaces are assigned to a single NIC, you can assign a different VLAN to each interface. If each interface has a different VLAN, it is accepted only if the destination IP address of the packet is the same as the IP address of the interface, and the packet's VLAN tag is the same as the interface's VLAN ID. If the VLAN ID of the interface is set to zero, the packets sent will not be tagged. There are usually two kinds of applications:

1, switch port configuration VLAN number, VNX do not configure. This is a typical configuration, using the default ID number 0 on VNX.

2, the switch and the data mover configuration VLAN tag, this VLAN technology in the configuration of standby data mover particularly useful. Because different data mover are typically located on different subnets, the standby data mover needs to connect to a single corresponding subnet to which they provide services by using VLAN tags.

Before creating a VLAN on the data mover, make sure that there are basic connections in your environment. Check the data mover port configuration and switch port configuration to verify that the speed and duplex values are end-to-end consistent and identical. If there is any value mismatch between the data mover and the switch, it can cause specific errors in the overall performance of the data mover and the entire network. After making sure that the above configuration is correct, you can follow these steps to correct the VLAN problem:

Step 1: The port is assigned the correct VLAN number and is checked on the switch.

3512xl#show VLAN Brief # (Cisco switch)

VLAN Name Status Ports

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

1 Default Active FA0/1, FA0/2, FA0/3, FA0/4

FA0/5, FA0/6, FA0/7, FA0/8

FA0/9, FA0/10, FA0/11, FA0/12

FA0/13, FA0/14, FA0/15, FA0/16

FA0/17, FA0/18, FA0/23, fa0/24

GI0/1, GI0/2

Ten VLAN0010 Active

One VLAN0011 Active

VLAN0012 Active

VLAN0013 Active

VLAN0014 Active

VLAN0015 Active

VLAN0016 Active

VLAN0017 Active

VLAN0018 Active

VLAN0019 Active

VLAN0020 Active

Step 2: Check that the label protocol is running correctly on the switch, ISL or 802.1Q protocol.

3512XL (config) #show run int fastethernet 0/1

Interface FASTETHERNET0/1

Switchport Trunk Encapsulation dot1q

Switchport mode Trunk

Step 3: Check to see if the VLAN trunk are active.

3512xl#show Interfaces Trunk

Step 4: Check the routing table to ensure that there are routes between the different VLANs.

router# show ip route

Codes:i-IGRP derived, R-rip derived, O-OSPF derived,

c-connected, s-static, E-EGP derived, B-BGP derived,

*-Candidate default route, IA-OSPF Inter area route,

I-is-is derived, Ia-is-is, u-per-user static route,

O-on-demand routing, m-mobile, p-periodic downloaded static route,

D-EIGRP, ex-eigrp External, E1-OSPF external type 1 route,

E2-OSPF external Type 2 route, N1-OSPF nssa external type 1 route,

N2-OSPF Nssa External Type 2 route

Gateway of last resort are 10.119.254.240 to network 10.140.0.0

O E2 10.110.0.0 [160/5] via 10.119.254.6, 0:01:00, Ethernet2

E 10.67.10.0 [200/128] via 10.119.254.244, 0:02:22, Ethernet2

O E2 10.68.132.0 [160/5] via 10.119.254.6, 0:00:59, Ethernet2

O E2 10.130.0.0 [160/5] via 10.119.254.6, 0:00:59, Ethernet2

E 10.128.0.0 [200/128] via 10.119.254.244, 0:02:22, Ethernet2

E 10.129.0.0 [200/129] via 10.119.254.240, 0:02:22, Ethernet2

You can find out most of the VLAN failures by using the above steps.