Users Guide

has no effect. If you configure the optimized booting-time capability and perform a reload of the
system, the LACP application sends PDUs across all the active LACP links immediately.
INTERFACE (conf-if-po-number) mode
Dell(conf-if-po-number)#lacp fast-switchover
Optimizing the Boot Time
You can reduce the booting time of a switch by using the fast boot feature. With the reduced time that is
taken to reboot the switch, upon a manually-initiated reload or an expected restart of the device, there is
minimal disruption in the traffic that is managed by the switch. Traffic outage is lowered considerably
(reduced to approximately 25 seconds in certain network deployments) when you enable this optimization
method while booting the device. By reducing the duration of traffic loss, the subscriber sessions are
processed and preserved in an effective and seamless way.
You can configure this capability on the switch that is deployed as a top-of-rack (ToR) switch. The ToR switch
is the single point of connection to the network for servers in that rack. This functionality of minimized reload
time is supported in a network deployment in which the servers are connected through a ToR, leaf and spine
unit or configuration setup. An exterior border gateway protocol (EBGP) session exists between the ToR and
leaf switch units, and between the leaf and spine units or nodes.
Booting Process When Optimized Boot Time
Mechanism is Enabled
When device running Dell Networking OS earlier than Release 9.3(0.0) is reloaded, the CPU and other
components on the board are reset at the same time. Therefore, the control plane and the forwarding plane
are impacted immediately. After the system boots up and re-initializes, the interfaces come up, control plane
protocols are reestablished, and the network topology information (such as routes, adjacency settings) is
learned and installed before the traffic resumes. In a typical network scenario, a traffic disconnection of 150
seconds or more usually occurs. When you employ the optimized booting functionality, the traffic outage
duration is reduced drastically.
Guidelines for Configuring Optimized Booting
Mechanism
Keep the following points and limitations in mind when you configure the fast boot capability:
• Fast boot is supported only when you perform an expected, stipulated reload by using the reload-
type normal-reload
command in Global Configuration mode or by using the reset command in
uBoot mode on a switch that is running Dell Networking OS Release 9.3(0.0) or later, or when you
perform a planned upgrade (and not an abrupt or unexpected shutdown) from an older release of Dell
Networking OS to Release 9.3(0.0) or later. Dell recommends that you do not downgrade your system
Flex Hash and Optimized Boot-Up 356