Cisco Asr 1000 Series Aggregation Services Routers Sip And Spa Software Configuration Guide, Cisco Ios - Cisco ASR 1000 Series Software Configuration Manual

Troubleshooting the Serial SPAs
Status Line Condition
Serial x is up, line protocol is down
OL-14127-17
Possible Problem
A local or remote router is
misconfigured.
Keepalives are not being sent by
the remote router.
A leased-line or other carrier
service problem has occurred
(noisy line or misconfigured or
failed switch).
A timing problem has occurred on
the cable.
A local or remote CSU/DSU has
failed.
Router hardware (local or remote)
has failed.
Cisco ASR 1000 Series Aggregation Services Routers SIP and SPA Software Configuration Guide, Cisco IOS XE
Serial Lines: show interfaces serial Status Line Conditions
Solution
Everest 16.5
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