At the egress LER, statistics are configured in the ingress data path of a terminating LSP by entering the LSP name, along with the ingress LER system interface address, with the config>router>mpls>ingress-statistics>lsp lsp-name sender ip-address command. Statistics collection is enabled in the ingress data path after the user executes the no shutdown command in the ingress-statistics context. By default, this function is in a shutdown state.
The LSP name must correspond to the name configured by the user at the ingress LER. Statistics cannot be configured if the LSP name contains a colon (:), which is used as a field separator by the ingress LER for encoding the LSP and path names into the RSVP Session Name field in the Session_Attribute object.
The no form of the ingress-statistics command disables statistics collection in the ingress data path and removes the accounting policy association from the RSVP LSP. Users can choose to disable statistics in the ingress data path while keeping the accounting policy association of the RSVP LSP with the config>router>mpls>ingress-statistics>lsp>shutdown command.
The same set of counters are updated for packets received over any path of the LSP. In the steady state, the counters are updated for packets received over the active path of the LSP. The active path can be the primary path, one of the secondary paths, the FRR detour path, or the FRR bypass path when the tail-end node is also the MP.
The LSP counters are maintained over the lifetime of the LSP as long as statistics are enabled. The user can clear the counters with the clear>router>mpls>lsp-ingress-stats ip-address lsp lsp-name command.
When a hierarchy of LSPs is in use, statistics collection on the outermost label corresponding to the tunneling LSP and on the inner labels, corresponding to the tunneled LSPs, are mutually exclusive. The outermost label takes precedence.
Because ingress data path statistics are not supported for an LDP FEC, there are no statistics collected for an LDP FEC, however if the LDP FEC is tunneled over an RSVP shortcut LSP that has LSP ingress statistics configured, the statistics are collected for the RSVP LSP
The user can enable statistics collection on a manual bypass LSP terminating on the egress LER. However, all LSPs whose primary path is protected by the manual bypass will not collect statistics when they activate forwarding over the manual bypass. If the user disables statistics collection on the manual bypass LSP, statistics collection, if enabled, is continued on the protected LSP when the bypass LSP is activated.
A flag in the output of the show command for the LSP statistics will indicate if there were no path state blocks (PSBs) that matched the specified LSP name at any given point in time. This could be due to the absence of the RSVP session or to the presence of a session type that is not supported; for example, the LSP name matched a point-to-multipoint LSP. The counters will show all zero values, which could otherwise be confused with an LSP with a valid matched PSB that is not receiving packets.