Router_B#debug isis update-packets
IS-IS Update related packet debugging is on
Router_B#
*Mar 1 00:53:16.043: ISIS-Upd: Rec L2 LSP 0000.0000.0003.01-00, seq 2, ht 1199,
*Mar 1 00:53:16.043: ISIS-Upd: from SNPA 000c.ce4b.c635 (Ethernet0)
*Mar 1 00:53:16.043: ISIS-Upd: LSP newer than database copy
*Mar 1 00:53:16.043: ISIS-Upd: no change
*Mar 1 00:53:26.263: ISIS-Upd: Rec L2 LSP 0000.0000.0003.00-00, seq 3, ht 1199,
*Mar 1 00:53:26.263: ISIS-Upd: from SNPA 000c.ce4b.c635 (Ethernet0)
*Mar 1 00:53:26.263: ISIS-Upd: LSP newer than database copy
*Mar 1 00:53:26.263: ISIS-Upd: no change