CRS-311 1:1 Redundancy Switch
Revision 7
Modem, RMI/TMI, and Switch Configuration MN/CRS311.IOM
4–18
Follow
these
steps
to
enable
Auto On
mode:
Step
Task
1
Go to the CONFIG
Æ
AUTO menu and select AUTO ON mode.
2
Verify that the Stored Event LED stops blinking.
4.6.1.2 Set Holdoff Period
A
holdoff
period
prevents
unwarranted
backups
due
to
an
intermittent
fault.
When
in
Auto
mode,
additional
delays
may
be
introduced
to
the
backup
procedure
by
setting
the
number
of
seconds
for
"holdoff"
before
the
faulted
Traffic
Modem
cedes
operation
to
the
Redundant
Modem
(
backup
),
or
operation
is
returned
from
the
Redundant
Modem
back
to
the
Traffic
Modem
(
restore
).
The
process
is
further
explained:
If
a
fault
occurs
in
the
Traffic
Modem,
and
the
Redundant
Modem
operation
is
fault
‐
free,
backup
is
initiated
once
the
configured
Backup
Holdoff
Period
lapses.
However,
if
the
fault
clears
within
the
holdoff’s
configured
timeframe,
no
transfer
of
operation
occurs.
Similarly,
if
a
fault
occurs
in
the
Redundant
Modem
while
it
is
online,
and
the
Traffic
Modem’s
operation
is
fault
‐
free,
restore
is
initiated
once
the
configured
Restore
Holdoff
Period
lapses.
The
default
holdoff
period
is
10
seconds
(a
minimum
of
1
second
and
a
maximum
of
99
seconds
is
allowed).
4.6.1.2.1
Set Backup Holdoff Period
If
the
Traffic
Modem
fails,
the
Switch
waits
for
the
backup
holdoff
time
to
determine
two
things:
1)
Does
the
Traffic
Modem
remain
faulted?
and
2)
Is
the
Redundant
Modem
not
exhibiting
the
same
fault?
If
the
answer
is
yes
to
both
questions
for
the
entire
Backup
Holdoff
Period,
then
the
Switch
first
bridges
the
faulted
Traffic
Modem
with
the
Redundant
Modem.
If
the
fault
is
sustained,
then
the
switchover
to
the
Redundant
Modem
is
completed
and
the
Redundant
Modem
carries
the
traffic.
There
will
be
no
switchover
if
the
Redundant
Modem
is
faulted.
Ensure
that
the
Holdoff
times
are
long
enough
(default
10
seconds)
for
the
Redundant
Modem
to
be
configured
and
to
lock
onto
the
signal.
Summary of Contents for CRS-311
Page 22: ...CRS 311 1 1 Redundancy Switch Revision 7 Preface MN CRS311 IOM xxii Notes...
Page 48: ...CRS 311 1 1 Redundancy Switch Revision 7 Cables and Connections MN CRS311 IOM 3 2 Notes...
Page 62: ...CRS 311 1 1 Redundancy Switch Revision 7 Cables and Connections MN CRS311 IOM 3 16 Notes...
Page 128: ...CRS 311 1 1 Redundancy Switch Revision 7 Front Panel Operation MN CRS311 IOM 5 20 Notes...
Page 166: ...CRS 311 1 1 Redundancy Switch Revision 7 Appendix A MN CRS311 IOM A 24 Notes...
Page 178: ...CRS 311 1 1 Redundancy Switch Revision 7 Appendix B MN CRS311 IOM B 12 Notes...
Page 186: ...CRS 311 1 1 Redundancy Switch Revision 7 Appendix C MN CRS311 IOM C 8 Notes...
Page 194: ...2114 WEST 7TH STREET TEMPE ARIZONA 85281 USA 480 333 2200 PHONE 480 333 2161 FAX...
