H3C S5500-28 C-EI-DC Installation Manual page 61

A ring connection is more reliable than a daisy chain connection. The failure of one link in a ring
connection does not affect the function and performance of the IRF, whereas the failure of one link in a
daisy chain connection causes the split of the IRF.
Figure 3-32 The daisy chain connection mode
Figure 3-33 The ring connection mode
Each of the devices comprising a ring connection or non-edge devices in a daisy chain connection
needs two 10 GE ports to connect other devices; therefore, you need to install two 1-port 10 GE XFP
interface modules on such devices.
Connect the cables
Before connecting the cables, determine the actual position of the member devices and the length of
the cables, and observe the following:
Understand the neighbor devices for one another
Install the interface modules in proper slots as needed. Each S5500-EI series provides two
expansion slots.
Determine the ports on different devices to be connected.
Note that:
When 2-port interface modules are used to constitute an IRF of switches and the ports are not
assigned to any aggregation group, ports of the interface module in slot 1 (MOD 1) can be
connected to ports of MOD 1 or MOD 2. However, the left port can be connected to only the right
Master
Slave IRF
Slave
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