Service Manual

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 from Release 9.3(0.0) to an earlier release that does not support the fast boot functionality because the system behavior
is unexpected and undened.
• Fast boot uses the Symmetric Multiprocessing (SMP) utility that is enabled on the Intel CPU on the S6000 Switch to enhance
the speed of the system startup. SMP is supported on the S6000 platform.
For the fast boot feature to reduce the trac disruption signicantly, the following conditions apply:
1. When LACP is used between the ToR switch and the adjacent devices, LACP is congured on these adjacent devices with a
timeout value of 90 seconds or longer.
2. BGP timers between the ToR switch and adjacent devices are set to high values (for example, a hold timeout of 180 seconds)
unless BGP graceful restart is used.
3. Before performing the planned reload, we recommend that the IPv6 Neighbor Discovery (ND) reachable timer is increased to a
value of 300 seconds or longer on the adjacent devices to prevent the ND cache entries from becoming stale and being
removed while the ToR goes through a CPU reset. This timer can be restored to its prior value after the ToR has completed its
planned reload.
4. The BGP protocol on the adjacent devices responds to network (link-state) changes and route advertisements quickly and
propagates these further up the network quickly. You might need to adjust the BGP timers on these devices.
5. Note that fast boot will operate even if some of the preceding conditions are not met. However, the duration of trac loss
might be longer.
6. Warm boot is supported because it enables faster convergence and reduced trac loss.
7. BGP graceful restart must be congured with GR time left to default (120 seconds) or higher. The BGP hold timer should be
congured as 10 seconds.
8. You must congure the LACP long timeout, which is the amount of time that a LAG interface waits for a PDU from the remote
system before bringing the LACP session down, to be higher than the default value.
9. Trac from North-South and South-North nodes are of line rate type.
10. Trac outage for a planned reboot is less than 30 seconds for 4000 routes of IPv4 and IPv6 trac for all of the following trac
directions. These trac patterns apply only to the S6000 platforms.
• South-North
• North-South
• East-West
• West-East
To the south of ToR switch, 96 servers can be linked. Up to 8 Multiprocotol BGP (MP-BGP) sessions to the servers are established.
You can congure a minimum of 2 MP-BGP sessions and a maximum of 8 MP-BGP sessions.
To the north of the ToR switch, up to 8 leaf nodes are connected. Up to 8 EBGP sessions for IPv4 and IPv6 for each leaf node are
congured. LACP is enabled between the ToR and leaf nodes, and the LACP long timer is set to the default value. You must
congure 96 ports to be 10-Gigabit Ethernet interfaces and 8 ports as 40-Gigabit Ethernet interfaces. You must congure the
switch to operate with an uplink speed of 40 Gigabit Ethernet per second.
Interoperation of Applications with Fast Boot and System States
This functionality is supported on the platform.
The following sections describe the application behavior when fast boot functionality is enabled:
LACP and IPv4 Routing
Prior to the system restart, the system implements the following changes when you perform a fast boot:
The system saves all dynamic ARP entries to a database on the ash drive.
Flex Hash and Optimized Boot-Up
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