Repeater (Hub) Management
24
In addition, the following counters listed in Table 6 are maintained on a
hub-wide basis:
Table 6:
Statistic Database Hub-Wide Counters
Power-up or reset clears the counters in the Statistics Database to zero. The
management agent will then maintain the counters until the next power-up/
reset, or until you clear one or more of the counters manually. Per MIB
specifications, all counters are 32 bits in precision. Note that since there is a
finite precision, counters may and will overflow (wrap around to zero) if left to
increment long enough. The amount of time necessary before a counter
overflows is dependent on the network traffic pattern, but is generally a
matter of several days to weeks. In applications where it is necessary to
maintain accurate records of hub traffic, it is important to periodically view,
record and then clear the statistics counters.
Working with the Management Agent
Starting a Session
To start a session with the management agent, either:
❑
Press the
RETURN/ENTER
key twice on the terminal connected to the
RS232 port
❑
Make a virtual circuit connection to the management agent (Telnet)
A “session” begins when either of these events occurs. Once in session, the
management agent and the Statistics Database are “locked” against other
session requests: that is, while connected in a virtual circuit, the hub will
ignore the RS232 port, and vice versa. This prevents unwanted simultaneous
access to the database.
If you have opted to use a password, the management agent will demand it at
the beginning of the session. If you have forgotten the password, you can
unlock the management agent by inserting the software cassette: no
password is ever required when the cassette is inserted in the firmware port.
The (optional) password used to access the system is not the same as the
password used to protect the downloading feature. See the discussion under
Download Menus later in this chapter.
Transmit Collisions
Frames with a collision occurring internal to the AT-3600 module;
i.e., two or more AT-3600 ports attempted to transmit at the same
time.
Jabber Lockups
Transmissions of excessive length that caused the AT-3600 mod-
ule to enter Jabber Lockup mode.
Note
