User guide

September 2009
Page 30 of 79 OmniSwitch 6400/6850/6855/9000/9000E—Release 6.4.2.R01
DNS Client
A Domain Name System (DNS) resolver is an internet service that translates host names into IP
addresses. Every time you enter a host name, a DNS service must look up the name on a server and
resolve the name to an IP address. You can configure up to three domain name servers that will be
queried in turn to resolve the host name. If all servers are queried and none can resolve the host name
to an IP address, the DNS fails. If the DNS fails, you must either enter an IP address in place of the
host name or specify the necessary lookup tables on one of the specified servers.
Dynamic VLAN Assignment (Mobility)
Dynamic assignment applies only to mobile ports and requires the additional configuration of VLAN
rules. When traffic is received on a mobile port, the packets are examined to determine if their content
matches any VLAN rules configured on the switch. Rules are defined by specifying a port, MAC
address, protocol, network address, binding, or DHCP criteria to capture certain types of network
device traffic. It is also possible to define multiple rules for the same VLAN. A mobile port is assigned
to a VLAN if its traffic matches any one VLAN rule.
DVMRP
Distance Vector Multicast Routing Protocol (DVMRP) is a dense-mode multicast routing protocol.
DVMRP—which is essentially a “broadcast and prune” routing protocol—is designed to assist routers
in propagating IP multicast traffic through a network. DVMRP works by building per-source broadcast
trees based on routing exchanges, then dynamically creating per-source, group multicast delivery trees
by pruning the source’s truncated broadcast tree.
End User Partitioning (EUPM)
EUPM is used for customer login accounts that are configured with end-user profiles (rather than func-
tional privileges specified by partitioned management). Profiles specify command areas as well as
VLAN and/or port ranges to which the user has access. These profiles are typically used for end users
rather than network administrators.
Ethernet Interfaces
Ethernet and Gigabit Ethernet port software is responsible for a variety of functions that support
Ethernet, Gigabit, and 10 Gigabit Ethernet ports. These functions include initialization of ports,
notifying other software modules when a port goes down, configuration of basic line parameters,
gathering of statistics for Ethernet and Gigabit Ethernet ports, and responding to administrative
enable/disable requests.
Configurable parameters include: autonegotiation (copper ports 10/100/1000), trap port link messages,
flood control, line speed, duplex mode, inter-frame gap, resetting statistics counters, and maximum and
peak flood rates.
Flood control is configurable on ingress interfaces (flood rate and including/excluding multicast).
Ethernet OAM
Ethernet OAM (Operation, Administration, and Maintenance) provides service assurance over a
converged Ethernet network. Ethernet OAM focuses on two main areas that are most in need by
service providers and are rapidly evolving in the standards bodies: Service OAM and Link OAM.
These two OAM protocols have unique objectives but are complementary to each other. Service OAM
provides monitoring and troubleshooting of end-to-end Ethernet service instances, while Link OAM
allows a provider to monitor and troubleshoot an individual Ethernet link. The end-to-end service
management capability is the most important aspect of Ethernet OAM for service providers.