Bull 1GB Intel Ethernet Switch Module, Инструкция по установке и эксплуатации

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Switch Management and Operating Concepts
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links have dropped out, the LAG will reconfigure itself with the new values from the received
LACPDUs.
It is important that when you configure LAGs, you should configure the LAGs and enable STP on
both partner devices before connecting the cables.
Distribution method
Link aggregation, or port trunking, enables several ports to be grouped together and to act as a single
link. This gives a bandwidth that is a multiple of a single-link bandwidth.
Port trunking is most commonly used to link a bandwidth intensive network device or devices, such
as a server, to the backbone of a network.
The switch module offers link aggregation on four external ports for up to two static trunk groups or
two LACP 802.3ad link aggregation groups. The trunked ports can be non-continuous (that is, have
non-sequential port numbers). All of the ports in the group must be members of the same VLAN. In
addition, the trunked ports must connect at the same speed in full-duplex mode.
Load balancing is automatically applied to the ports in the trunked group, and a link failure within
the group causes the network traffic to be directed to the remaining links in the group.
The STP will treat a port trunking group as a single link on the switch level. On the port level, the
STP will use the port parameters of the Master Port in the calculation of port cost and in determining
the state of the port trunking group. If two redundant port trunking groups are configured on the
switch module, STP will block one entire group in the same way STP will block a single port that
has a redundant link.
Dynamic Host Configuration Protocol (DHCP)
The Dynamic Host Configuration Protocol (DHCP) can reduce the administrative burden of
assigning and maintaining IP address information. DHCP provides reliable and simple TCP/IP
network configuration, ensures that address conflicts do not occur, and helps to conserve the use of
IP addresses through centralized management of address allocation.
Dynamic address allocation enables a client to be assigned an IP address from a pool of free
addresses. Each address is assigned with a lease and a lease expiration period. The client must renew
the lease to continue using the assigned address. Dynamically assigned addresses can be returned to
the free address pool if the computer is not being used, if it is moved to another subnet, or if its lease
expires. Usually, network policy ensures that the same IP address is assigned to a client each time
and that addresses returned to the free address pool are reassigned.
When the address lease expires, the DHCP client enters the renewing state. The client sends a
request message to the DHCP server that provided the address. The DHCP server sends an
acknowledgement that contains the new lease and configuration parameters. The client then updates
its configuration values and returns to the bound state.
When the DHCP client is in the renewing state, it must release its address immediately in the rare
event that the DHCP server sends a negative acknowledgment. The DHCP server sends this message
to inform a client that it has incorrect configuration information, forcing it to release its current
address and acquire new information.
If the DHCP client cannot successfully renew its lease, the client enters a rebinding state. The client
then sends a request message to all DHCP servers in its range, attempting to renew its lease. Any
DHCP server that can extend the lease sends an acknowledgment containing the extended lease and
updated configuration information. If the lease expires or if a DHCP server responds with a negative