Administrator Guide

• Lossless connectivity: VMs require the connectivity to the storage network to be lossless always. When a planned upgrade of the
network nodes happens, especially with top-of-rack (ToR) nodes where there is a single point of failure for the VMs, disk I/O
operations are expected to occur in 20 seconds. If disk in not accessible in 20 seconds, unexpected and undefined behavior of the
VMs occurs. You can optimize the booting time of the ToR nodes that experience a single point of failure to reduce the outage in
traffic-handling operations.
RRoCE has IP headers. RRoCE is bursty and uses the entire 10-Gigabit Ethernet interface. Although RRoCE and normal data traffic are
propagated in separate network portions, it may be necessary in certain topologies to combine both the RRoCE and the data traffic in a
single network structure. RRoCE traffic is marked with dot1p priorities 3 and 4 (code points 011 and 100, respectively) and these queues
are strict and lossless. DSCP code points are not tagged for RRoCE. Both ECN and PFC are enabled for RRoCE traffic. For normal IP or
data traffic that is not RRoCE-enabled, the packets comprise TCP and UDP packets and they can be marked with DSCP code points.
Multicast is not supported in that network.
Sample Configurations
Figure 40. Configure DCB end-to-end on this setup
Sample configuration for RoCE traffic
MXL Fabric B1 and B2 Switches (RoCE Traffic Only)
!
dcb enable
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Flex Hash and Optimized Boot-Up