System Manager 11.70.2 - Considerations for assigning IP addresses

By default, controllers ship with DHCP enabled on both network ports. You can assign static IP addresses, use the default static IP addresses, or use DHCP-assigned IP addresses. You also can use IPv6 stateless auto-configuration.

Note: IPv6 is disabled by default on new controllers, but you can configure the management port IP addresses using an alternate method, and then enable IPv6 on the management ports using ThinkSystem System Manager .

When the network port is in a "link down" state, that is, disconnected from a LAN, the system reports its configuration as either static, displaying an IP address of 0.0.0.0 (earlier releases), or DHCP enabled with no IP address reported (later releases). After the network port is in a "link up" state (that is, connected to a LAN), it attempts to obtain an IP address through DHCP.

If the controller is unable to obtain a DHCP address on a given network port, it reverts to a default IP address, which might take up to three minutes. The default IP addresses are as follows:

SAN OS 11.50.3 or earlier:
- Controller A, port 1: 192.168.128.101
- Controller B, port 1: 192.168.128.102
- Subnet mask: 255.255.0.0
SAN OS 11.60.2 or later:
- Controller A, port 1: 169.254.128.101
- Controller B, port 1: 169.254.128.102
- Subnet mask: 255.255.0.0

When assigning IP addresses:

Reserve Port 2 on the controllers for technical support usage. Do not change the default network settings (DHCP enabled).
To set static IP addresses, use ThinkSystem System Manager. After a static IP address is configured, it remains set through all link down/up events.
To use DHCP to assign the IP address of the controller, connect the controller to a network that can process DHCP requests. Use a permanent DHCP lease.

Note: The default addresses are not persisted across link down events. When a network port on a controller is set to use DHCP, the controller attempts to obtain a DHCP address on every link up event, including cable insertions, reboots, and power cycles. Any time a DHCP attempt fails, the default static IP address for that port is used.