Managing tenant networks

Tenant networks are managed through logical networks, network connections, and endpoint groups within an infrastructure. This page covers how connections, link aggregation and redundancy work at the tenant level.

Network connections

A network connection links a server instance group, VM instance group or endpoint group to a logical network. When creating a connection you can configure:

• Tagged/Untagged — whether the VLAN tag is preserved on the interface
• Access mode — how the port is configured on the switch
• MTU — the maximum transmission unit for the connection
• Provides default route — whether this network provides the default gateway
• Disable auto IP allocation — opt out of automatic IP assignment
• Redundancy — the redundancy configuration (see below)
• DNS — DNS records to provision for the connection

Redundancy configuration

When connecting endpoints to a logical network, you can specify a redundancy configuration that controls how multiple ports are bonded:

Redundancy Mode	Description
active-backup	One link is active, the other is standby. Traffic fails over if the active link goes down.
active-active	All links are active simultaneously, providing increased bandwidth and redundancy.

Each mode can use one of these implementation types:

Implementation Type	Description
link-aggregation	Bundles multiple links on the same switch using LACP.
distributed-link-aggregation	Bundles links across a switch pair (MLAG/VLT/VPC). Requires a switch pair.
ecmp	Uses Equal-Cost Multi-Path routing across multiple links.

Details on link aggregation

If the user chooses to connect two or more ports to the same logical network, a link aggregation will be created on the switches and a bond interface will be created on the server:

1. If the two ports lead to different switches defined as a switch pair then an M-LAG or equivalent multi-chassis link aggregation (distributed-link-aggregation) will be created. LACP type 4 will be used as negotiation protocol.

2. If the two ports lead to two different switches that are configured in “stacked” configuration in which case a single switch record is registered in MetalSoft, the system will create regular link-aggregations, using LACP type 4.

3. If the two ports lead to the same switch a simple link-aggregation will be created on the respective switch. The link will be configured using LACP type 4.

To ensure consistent behavior, the LACP priority will be higher on the port with the lower index so that if the LACP protocol cannot negotiate with the server (such as during the boot process) the fallback port will always be port with index #0.

Link aggregations at the fabric level (between switches, as opposed to between servers and switches) are now managed as standalone resources. See Managing BGP Sessions and Link Aggregations for details.

How server interface indexes are allocated

To ensure consistent behavior the network ports of the servers will always have indexes based on the switch hostname and then the switch port in lexicographic order irrespective of the actual order in the server. For example if a server is connected to two switches with hostnames sw1 and sw2 and connected to Ethernet10 on both, the port connected to sw1 will always be port index #0 and the port connected to sw2 will always be port #1. If the same server is connected to sw1 Ethernet11 and sw1 Ethernet10 the second port will be index #0 and the first one will be #1.

OS Interface Index

MetalSoft provides OS index information for interfaces which is what VMWare ESXI uses to name the interfaces thus the OS index 1 will be the vmk1 interface.

Virtualization networking

MetalSoft uses a novel networking approach for the virtualization by tying the VMs into the same network as bare metal servers. This means that the network admin can reuse the network profiles, subnets, external connections etc. To learn more go to Managing VM Pools

Where to go from here:

• Network topology
• Managing network profiles
• Managing BGP Sessions and Link Aggregations