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6. If the path message for the primary LSP path indicated link protection desired, and no
7. If the PLR node successfully makes an association, it must set the "local protection
8. For all primary LSP that requested FRR protection but are not currently associated with a
If the user disables dynamic-bypass tunnels on a node while dynamic bypass tunnels were
activated and were passing traffic, traffic loss will occur on the protected LSP. Furthermore, if no
manual bypass exist that satisfy the constraints of the protected LSP, the LSP will remain without
protection.
If the user configures a bypass tunnel on node B and dynamic bypass tunnels have been disabled,
LSPs which have been previously signaled and which were not associated with any manual bypass
tunnel, for example, none existed, will be associated with the manual bypass tunnel if suitable.
The node checks for the availability of a suitable bypass tunnel for each of the outstanding LSPs
every time a RESV message is received for these LSPs.
If the user configures a bypass tunnel on node B and dynamic bypass tunnels have not been
disabled, LSPs which have been previously signaled over dynamic bypass tunnels will not
automatically be switched into the manual bypass tunnel even if the manual bypass is a more
optimized path. The user will have to perform a make before break at the head end of these LSPs.
If the manual bypass goes into the down state in node B and dynamic bypass tunnels have been
disabled, node B (PLR) will clear the "protection available" flag in the RRO IPv4 sub-object in
the next RESV refresh message for each affected LSP. It will then try to associate each of these
LSPs with one of the manual bypass tunnels that are still up. If it finds one, it will make the
association and set again the "protection available" flag in the next RESV refresh message for
each of these LSPs. If it could not find one, it will keep checking for one every time a RESV
message is received for each of the remaining LSPs. When the manual bypass tunnel is back UP,
the LSPs which did not find a match will be associated back to this tunnel and the protection
available flag is set starting in the next RESV refresh message.
If the manual bypass goes into the down state in node B and dynamic bypass tunnels have not
been disabled, node B will automatically signal a dynamic bypass to protect the LSPs if a suitable
one does not exist. Similarly, if an LSP is signaled while the manual bypass is in the down state,
the node will only signal a dynamic bypass tunnel if the user has not disabled dynamic tunnels.
When the manual bypass tunnel is back into the UP state, the node will not switch the protected
LSPs from the dynamic bypass tunnel into the manual bypass tunnel.
7950 SR OS MPLS Configuration Guide
manual bypass was found after step 1, and/or no dynamic bypass LSP was found after
performing Step 3, the primary LSP will have no protection and the PLR node must clear
the "local protection available" flag in the IPv4 address sub-object of the RRO starting in
the next RESV refresh message it sends upstream. The PLR will not search for a node-
protect' bypass LSP in this case.
available" flag in the IPv4 address sub-object of the RRO starting in the next RESV
refresh message it sends upstream.
bypass tunnel, the PLR node on reception of RESV refresh on the primary LSP path
repeats Steps 1-7.
MPLS and RSVP
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