User guide

Radiance 1000Mbps Redundant Interface Line Cards 21
Solution
To implement single-strand failover protection, enable the following DIP
switches
*
: RED, LINK, AUTO, and TX on each card. The R752 line cards
automatically perform the following operations to restore data activity.
• Line Card A switches its active port from Primary to Secondary.
• Line Card A stops transmitting data and link pulses through the Primary port.
• Line Card B switches its active port from Primary to Secondary.
Bi-directional traffic is now restored.
LK
AT
LK
AT
LK
AT
S
E
C
P
R
I
M
A
I
N
S
E
C
P
R
I
R752
R752
M
A
I
N
LK
AT
LK
AT
LK
AT
Line Card A
Line Card B
no data, no linkactive port
switches to
Secondary
active port
switches to
Secondary
• Line Card A restarts transmitting link pulses on the Primary port.
Result
All data communications continue in both directions with the Secondary port
active on both cards.
Revert to Primary
The R752 cards will revert to having the Primary port active if the following
conditions are met:
• Both cards receive valid link pulses on the Primary port.
• Both cards detect data on the Primary port.
Alternate Solution
If you do not want bidirectional traffic resumed through the Secondary port
when a single strand of fiber breaks, do NOT enable the four switches (RED,
LINK, AUTO, and TX) at the same time on both cards. This results in the
transfer of data from B to A, but not from A to B.
*The SONAR switch may also be enabled.