Chapter 13 LANE Services
Avaya M770 ATM Switch User’s Guide 185
The LES and BUS in an Avaya M770 ATM Switch
Each module can provide up to 16 combined LES/BUS pairs. By default, all
modules have one Ethernet LES/BUS named “default,” that will try to register with
the LECS. The M770 ATM Switch LESes support a proprietary automatic LES
address determination method. Therefore, all the M770 ATM Switch LESes can
automatically register with an M770 ATM Switch LECS. The benefit of this is that a
LES can be re-located without reconfiguring the LECS or the LECs on the ELAN
hosted by the re-located LES.
The M770 ATM Switch LESes support two proprietary mechanisms for Resilient
and Distributed LES/BUS services as described below. These features require that
the LECS, LES and BUS will be hosted on M770 ATM Switch modules.
Note: Since by default, all modules have a LES/BUS named “default,” as soon as the
number of modules in your entire network exceeds the maximum number of LESes
per ELAN as defined in lane elan max les (default 5, maximum 10), you
should start deleting or disabling servers
LUNI 2.0 capability
By default, a LES in M770 ATM switch has LUNI 2.0 capability. This means that
when it registers to an M770 ATM LECS, it will try to determine that the entire
ELAN will be LUNI 2.0 capable (if the LECS LUNI 2.0 was 'auto', and if this LES
was registered first, it will actually determine that). When a LUNI 1.0 client tries to
register to this LES, the LES will accept it. However, if the LES is not a LUNI 2.0
capable (i.e. LUNI 1.0 only), then when a LUNI 2.0 client tries to register, it will be
told to work in LUNI 1.0 mode.
Proprietary resilient standby LESes
The M770 ATM Switch LECS supports a proprietary standby LESes. This will
enable resiliency of the LES/BUS in case the module hosting the LES/BUS fails. You
can configure up to 10 modules to host the same ELAN name (for example,
“default”). Only the first LES to contact the LECS will host the “default” ELAN. All
other LESes will provide standby support for the ELAN.
Should the original LES fail for any reason, one of the standby LESes will become
the main LES and host the “default” ELAN. This ensures that the ELAN remains up
and available to all LECs on the ELAN.
Note: Avaya strongly recommends that you use distributed LES/BUS services instead
of resilient.