A table of outage related events generated by this router.
Conceptual row entries are dynamically added into this
table when outage related events occur.
Entries are stored in FIFO order. When the maximum number
of entries has been reached in the table, the oldest entry
in the table is removed immediately.
When a table is reduced to a smaller size N, the oldest
entries are immediately removed from the table leaving
a maximum of N entries.