ntp refclock GPS using cellular 5G PIM

[emuman100]

According to this, I should be able to utilize the cellular interface's GPS as an ntp refclock but the refclock command is missing completely.

I'm running 17.09.07b IOS-XE on a Cisco 8200L with P-5GS6-GL. The cellular controller config is:

controller Cellular 0/2/0
lte dyinggasp sms send <snip>
lte sms archive path <snip>
lte gps mode standalone
lte gps nmea

When under configuration mode, ntp refclock does not exist:

(config)#ntp ?
access-group Control NTP access
allow Allow processing of packets
authenticate Authenticate time sources
authentication-key Authentication key for trusted time sources
broadcastdelay Estimated round-trip delay
clock-period Length of hardware clock tick
leap-handle To handle the leap seconds
logging Enable NTP message logging
master Act as NTP master clock
max-associations Set maximum number of associations
maxdistance Maximum Distance for synchronization
mindistance Minimum distance to consider for clockhop
orphan Threshold Stratum for orphan mode
panic Reject time updates > panic threshold (default 1000Sec)
passive NTP passive mode
peer Configure NTP peer
server Configure NTP server
source Configure interface for source address
trusted-key Key numbers for trusted time sources

Anyone know if there are some undocumented steps or if I need an IOS-XE newer than Cupertino?

Thanks!

[Jens Albrecht · Accepted solution]

Hello @emuman100,

the document you mention refers to the Cisco Catalyst IR1800 Rugged Series Routers.

Similar to the support for PTP (Precision Time Protocol) and high-accuracy timekeeping capabilities, these features are typically found on rugged/industrial platforms (e.g., IR1101, IR1800) where the cellular controller is tightly integrated with platform-level GPS.

Sub-microsecond precision time synchronization is a common requirement found in industrial, automation, and utility networks, not on standard enterprise networks.

I am not aware of any enterprise-class plattform that offers this type of feature sets.

HTH!

[balaji.bandi]

You need to refer the Cat8K model configuration guide to get accurate command to work :

https://www.cisco.com/c/en/us/td/docs/iosxr/cisco8000/timing/configuration/b-timing-sync-configuration-ios-xr-8000/m-network-time-protocol.html

[Jens Albrecht]

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@balaji.bandi wrote:

You need to refer the Cat8K model configuration guide to get accurate command to work :

https://www.cisco.com/c/en/us/td/docs/iosxr/cisco8000/timing/configuration/b-timing-sync-configuration-ios-xr-8000/m-network-time-protocol.html

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This is not correct.

That document refers to the IOS-XR based Catalyst 8000 Service Provider routers.

The IOS-XE based enterprise-class Catalyst 8000 Router Series is a completely different platform, running different software with totally different feature sets!

It is indeed confusing that Cisco uses the same name for 2 completely different platforms and with the launch of the brand-new Catalyst 8000 Secure Router Series things even get worse.

[balaji.bandi]

@Jens Albrecht  good catch -- that is my wrong reference i mean to say IOS XE 8K model