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px12 Advanced Network Configuration Guide
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Improved manageability: VLAN removes dependency on the physical network and topology by
creating a logical network to connect physically diverse workgroups within a single broadcast
domain. It’s easy, flexible, and less costly to modify a logical network in changing
environments. Large networks can be managed centrally regardless of physical locations of
devices.
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Network tuning and simplification of configurations: Administrators can fine-tune the network
infrastructure at a more granular level without disrupting other logical networks. When network
issues arise, administrators can quickly isolate the problematic network to identify the root
cause. Additionally, software configurations can be standardized and deployed easily across
computers and users within the same network.
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Enhanced security: Segmenting users into separate VLANs helps restrict user access to
sensitive information at the network layer, providing an extra layer of data security. Traffic
between VLANs can be easily controlled using router features such as access lists.
NIC BONDING CONFIGURATION
NIC bonding addresses two problems with Ethernet connections: bandwidth limitations and lack of
redundancy. Ethernet bandwidth requirements do not scale linearly; they have historically increased
by an order of magnitude each generation (10/100/1000/10000 Mbit/sec Ethernets). When the
network bandwidth ceiling is reached, upgrading to the next generation is very expensive. The
alternative solution is to combine two or more physical Ethernet links into one logical link for an
aggregated bandwidth. In a typical port-cable- port connection, there are three single points of
failure whether the connection is between computer and switch or between switches. NIC bonding
provides a solution to this problem by eliminating the single points of failure. Failover can happen
automatically in the event of a port or cable failure.
NIC bonding can be configured in different modes. Some typical modes include:
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NIC failover: this mode provides adapter fault tolerance through automatic failovers from an
active NIC to a standby NIC in the case of switch port, cable, or NIC failure. No switch
configuration is required for this mode. It works with any switch or hub.
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Adaptive transmit load balancing (TLB): this mode provides transmit traffic load balancing and
fault tolerance in the event of switch port, cable, or NIC failure. Transmit load is balanced
across member NICs, but normally only one NIC accepts all receive load. No switch
configuration is required for this mode. It works with any switch or hub.
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Adaptive load balancing (ALB): this mode provides both transmit and receive traffic load
balancing and fault tolerance. Both transmit and receive loads are balanced across member
NICs. No switch configuration is required for this mode. It works with any switch or hub.
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Static link aggregation (SLA): this mode bundles or channels NIC ports together and shows
them as a single link. This increases the total bandwidth for the link and provides fault
tolerance in the event of a switch port, cable, or NIC failure. All member NICs must be linked
to the same switch, and the switch must be configured for SLA before the bond is created. It
works with Cisco switches that have channeling mode set to ON, Intel switches capable of link
aggregation, and other switches capable of static IEEE 802.3ad.
