CDOT Tip #8

In order to clarify CDOT’s networking architecture, here’s a basic explanation of each object involved.

1.       Node SVM: aggregates, disks, and ports belong to the node Storage Virtual Machine.

2.       Data SVM: volumes, qtrees, and data LIFs belong to the data SVM.

3.       Ports: You issue commands to the three types of ports the same way.  Those three types are:

a.       Physical Port: at the Physical Port level you can set the MTU or Flow Control. 

b.      Ifgrp (interface group): these are now named in the convention “a0a.”  Ifgrps are made up of ports and exist for redundancy and load balancing.  You can set all the port properties here (changes will override the member ports). Ifgrps have these properties: Role, MTU, Flow Control, Duplex, and load balancing policy.

c.       VLAN: You can assign a VLAN to a port or ifgroup, which creates a virtual port.  VLANS have mostly the same properties as Ifgrps.

4.       LIF (logical interface): a LIF has a Name, an IP address, netmask, Role and a Home Port.  A LIF belongs to a Failover Group and a Routing Group

5.       Failover Group: list of ports a LIF is allowed to be on.  You usually want one for each node management, one for cluster management, and one for 10GbE data.

6.       Routing Group:  these allow a SVM to have different gateways for different VLANs or networks.  A Routing Group has these properties:  a name, address/mask combo (in CIDR notation), role, and metric.   Name data routing groups starting with a d, intercluster routing groups with an i, and cluster network routing groups with a c.

One thing you’ll notice is that Role is now important.  There are several Roles you can assign: Management, Data, Cluster, and Intercluster.  You’ll need to make sure the ports, LIFs, Failover Groups, and Routing Groups are in harmony as to their Role setting.

Also, one last point: SnapVault and SnapMirror are performed using the node’s Intercluster LIFs.  Your data SVMs will not have any intercluster LIFs.