Symmetricom TimeHub 5500 User Manual

097-55501-01 Revision M – January 2009 TimeHub 5500 User’s Guide 239
Chapter 5 Maintaining the TimeHub 5500
Replacing Cards
Replacing the Output Driver Card
To replace the Output Driver card, follow the procedure below while referring to
Figure 5-6.
1. Put on a properly grounded ESD wrist strap.
2. Using a #2 Phillips-head or Pozidrive screwdriver, loosen the captive screws on
the front panel.
3. Remove the card from the shelf.
4. Insert the replacement card into the shelf: ensure that the card aligns properly
with its mating backplane connector; push the card into place until it is fully
seated into the backplane connectors.
5. Wait for the Power LED to light, the DS1 and/or CC LEDs to light according to the
Output Connector cards installed, and the Fail and Alarm LEDs to turn off.
6. Press the Cutoff pushbutton on the Management card several times.
7. Verify that any alarm conditions are cleared.
8. Tighten the captive screws at the top and bottom of the card.
Replacing the Management Card
When you replace an existing Management Card 090-55542-01 with a replacement
Management Card, the newly-inserted Management Card may not immediately
communicate via Ethernet. This could be mistakenly perceived as a Dead On
Arrival unit due to communication failure.
The original IMC card installed in the TimeHub has a user-assigned IP address
along with a hard-wired MAC address. This information is saved in the ARP table on
the network router. When a new IMC card is plugged in, the network router starts
querying the new IMC card for IP and MAC address information. Since the new IMC
card has an initial IP address of “0.0.0.0”, certain routers consider this IP and MAC
address to be harmful to the network and therefore disable the port associated with
the new IMC card for a period of time. This lockout period can vary depending on
the router’s configuration and can take up to 5 minutes to restore.
When a new IMC card is introduced to the network with the old IP address of the
original IMC card, there is a transition period for the network router to associate the
IP address with the new IMC card’s MAC address. The router must update the ARP
table to reflect the change in the MAC address. While the network router is updating
the ARP table, all Ethernet communications with the IMC card will result in failure.
The time it takes to complete this update varies depending on the sophistication of
the router.

Symmetricom TimeHub 5500 Specifications

General

Brand	Symmetricom
Model	TimeHub 5500
Category	Data Loggers
Language	English