Isf Merge And Split - Raisecom ISCOM2600G-HI (A) Series Configuration Manual

Raisecom
ISCOM2600G-HI (A) Series Configuration Guide
Role election
The process for determining a member device as the master or backup device is called role
election, which occurs when the topology changes as below:




Roles are elected in the following roles in descending order:
1.
2.
3.
Role election follows the previous rules from the first rule. If multiple member devices are
equivalently optimal according to a rule, the following rules will not stop working until a
unique optimal member device is elected. Then, this optimal member device is the master, the
second optical one is the backup device, and others are slave devices.
After role election is complete, the master device sends a Config packet to check whether
communication is normal. After the ISF is completely established, it enters management and
maintenance phase.
When two ISF merge, ISF election will occur by following rules of role election. The
devices in the loser ISF join the winner ISF as the backup device or slave devices,
and forming a new ISF with the master member device. The restart during ISF merge
is manually operated.
No matter a device forms an ISF with other devices or joins an ISF, it will be initialized
and restarted by using configurations of the master device to synchronize with the
master device if it works as the slave device, regardless of what configurations it has
nor whether it has saved current configurations.

3.2.3 ISF merge and split

ISF merge
ISF merge occurs under the following conditions:


ISF is established.
A device joins the ISF.
The master device leaves or fails.
Two ISFs are merged.
The current master device, even if a new member device has a higher priority (when an
ISF is established, all member devices consider themselves as the master because there is
no master. Thus this rule is skipped for the next rule).
The device that has been running for the longest time (the up time of each device is
carried by the ISF Hello packet)
The device with a lowest bridge MAC address
A device is powered on but it is not connected to the ISF. In this case, it will be elected
as the backup device or slave device (depending on whether there is a slave device in the
ISF because the ISF can contain only one backup device). For example, device A is
elected as the master device (ISF takes effect upon power-on, so it elects itself as the
master device if there is no new member); then, device B joins the ISF after being
restarted, and is elected as the backup device (according to role election rule 1). The
MAC address of the ISF is that of device A.
The new device is already the master device (ISF is already effective. The device is
connected with the other device). There two devices will compete to elect for the master
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