Juniper JUNOSE SOFTWARE 11.0.X - LINK LAYER CONFIGURATION GUIDE 4-1-2010 Configuration Manual page 305

MLPPP bundles with only one link per bundle when configuring static
MLPPP-over-PPPoE-over-Ethernet. When you create multilink bundles in a
static MLPPP-over-PPPoE-over-Ethernet configuration, PPPoE is unable to
direct the PPPoE Active Discovery Initiation (PADI) packets received from
the MLPPP bundle links on the client to the appropriate (matching) links in
the MLPPP bundle on the server. As a result, the connections between bundle
links become crossed, and the bundle does not come up as expected. Creating
MLPPP bundles with only a single link for this configuration ensures a
one-to-one correspondence between a PPPoE subscriber and its associated
link, and guarantees that the MLPPP bundle comes up properly.
MLPPP bundles with only a single link per bundle are not required for static
MLPPP-over-PPPoE-over-Ethernet with VLAN configurations if all of the links
in a bundle have the same VLAN ID that is unique across all MLPPP bundles
configured on the line module.
On all E Series ATM module combinations that support MLPPP, you can configure:
MLPPP bundles with one or more links per bundle for dynamic
MLPPP-over-multiple PPPoE subinterfaces-over-one PPPoE major
interface-over-ATM 1483 subinterface configurations.
MLPPP bundles with only one link per bundle when configuring static
MLPPP-over-multiple PPPoE subinterfaces-over-one PPPoE major
interface-over-an ATM 1483 subinterface. In this configuration, you can stack
multiple PPPoE subinterfaces over a single PPPoE major interface.
Typically when you create ATM PVCs on an ATM module, there is a
one-to-one correspondence between a PPPoE subscriber and the ATM PVC
with which the subscriber is associated. However, in configurations with
multiple PPPoE subinterfaces stacked over a single PPPoE major interface,
crossed MLPPP bundle link connections can occur, as is the case with the
ES2-S1 GE-4 IOA, and the bundle does not come up as expected. Creating
MLPPP bundles with only a single link for this configuration ensures a
one-to-one correspondence between a PPPoE subscriber and its associated
link, and guarantees that the MLPPP bundle comes up properly.
MLPPP bundles with only a single link per bundle are not required for static
MLPPP-over-multiple PPPoE subinterfaces-over-one PPPoE major
interface-over-ATM 1483 subinterface configurations if all PPPoE
subinterfaces stacked over the same PPPoE major interface belong to the
same bundle.
NOTE: For information about the modules that support MLPPP on ERX14xx models,
ERX7xx models, and the ERX310 router, see ERX Module Guide, Appendix A, Module
Protocol Support. For information about the modules that support MLPPP on the
E120 and E320 routers, see E120 and E320 Module Guide, Appendix A, IOA Protocol
Support.
Chapter 8: Configuring Multilink PPP
Supported MLPPP Features
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