Information Technology Reference
In-Depth Information
Getting to the Edit Settings Dialog Box for the Uplinks Group
Getting to the Edit Settings dialog box for a distributed switch's uplink group, like the one shown
in Figure 5.70, might seem a bit unintuitive at fi rst. h e trick is to select (or highlight) the uplink
group in Topology view and then click the Edit Distributed Port Group Settings icon. As far as we
know, this is the only way in the vSphere Web Client to get to this dialog box—it's not accessible
from the Actions menu, nor is it available through any right-click menu.
You must coni gure LACP on the physical switch to which the ESXi host is connected; the
exact way you enable LACP will vary from vendor to vendor. The Mode setting shown in
Figure 5.70—which is set to either Active or Passive—helps dictate how the ESXi host will com-
municate with the physical switch to establish the link aggregate:
When LACP Mode is set to Passive, the ESXi host won't initiate any communications to the
physical switch; the switch must initiate the negotiation.
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When LACP Mode is set to Active, the ESXi host will actively initiate the negotiation of the
link aggregation with the physical switch.
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You can probably gather from this discussion of using LACP with a version 5.1.0 vSphere
Distributed Switch that only a single link aggregate (a single bundle of LACP-negotiated links)
is supported and LACP is enabled or disabled for the entire vSphere Distributed Switch.
When you upgrade to a version 5.5.0 vSphere Distributed Switch, though, the LACP support
is enhanced to eliminate these limitations. Version 5.5.0 distributed switches support multiple
LACP bundles, and how those LACP bundles are used (or not used) can be coni gured on a
per-distributed port group basis. Let's take a look at how you'd coni gure LACP support with a
version 5.5.0 distributed switch.
With a version 5.5.0 distributed switch, a new LACP section appears in the Settings area of
the Manage tab, as you can see in Figure 5.71. From this area, you'll dei ne one or more link
aggregation groups (LAGs), each of which will appear as a logical uplink to the distributed port
groups on that distributed switch. vSphere 5.5 supports multiple LAGs on a single distributed
switch, which allows administrators to dual-home distributed switches (connect distributed
switches to multiple upstream physical switches) while still using LACP. (There are a few limita-
tions, which we'll describe near the end of this section.)
Figure 5.71
vSphere 5.5's
enhanced LACP
support eliminates
many of the limita-
tions of the support
found in
vSphere 5.1.
