某局点使用铷钟作为ntp服务器时钟同步失败经典案例

不涉及。

无

S10500作为客户端，向服务器同步时钟，如果用我们自己设备作为ntp服务器，S105可以ntp同步成功，但客户使用铷钟作为ntp服务器无法同步成功，但是此时华为的交换机能向铷钟同步成功。

<交换机>display ntp-service status

Clock status: unsynchronized

Clock stratum: 16

Reference clock ID: none

Clock jitter: 0.000000 s

Stability: 0.000 pps

Clock precision: 2^-23

Root delay: 0.00000 ms

Root dispersion: 0.22888 ms

Reference time: 00000000.00000000 Mon, Jan 1 1900 8:05:52.000

System poll interval: 8 s

服务器问题，没有正确填写REFID导致，由于收到服务器的报文中的refid是0.0.0.0导致和我们计算的refid一致，这种情况我们认为对端设备是以我们为服务器的，产生一种环路，所以我们不会同步对端的时间。

<交换机>debugging ntp-service all

<交换机>*Oct 24 14:56:17:374 2022 交换机 NTP/7/PACKET_SEND: -MDC=1; Flushing packet, 1 items

*Oct 24 14:56:54:107 2022 交换机 NTP/7/PACKET_SEND: -MDC=1;

packet to 10.0.13.2, length: 48

leap: 3, version: 3, mode: 3, vrfindex: 0

stratum: 16, poll: 6, precision: 2^-23

rdel: 0.000, rdsp: 0.992, refid: INIT

reftime: 00000000.00000000 Mon, Jan 1 1900 8:05:52.000

orgtime: e700b5ac.82872afc Mon, Oct 24 2022 14:56:44.509

rectime: e700b573.1c0b6ea0 Mon, Oct 24 2022 14:55:47.109

xmttime: e700b5b6.1b66cb92 Mon, Oct 24 2022 14:56:54.107

*Oct 24 14:56:54:109 2022 交换机 NTP/7/PACKET_RECV: -MDC=1;

packet from 10.0.13.2 to 200.200.200.6 on Route-Aggregation100

leap: 0, version: 3, mode: 4, vrfindex: 0

stratum: 2, poll: 6, precision: 2^-10

rdel: 0.000, rdsp: 0.000, refid: 0.0.0.0

reftime: e700b5ee.81f1497e Mon, Oct 24 2022 14:57:50.507

orgtime: e700b5b6.1b66cb92 Mon, Oct 24 2022 14:56:54.107

rectime: e700b5ef.81ee99a0 Mon, Oct 24 2022 14:57:51.507

xmttime: e700b5ef.81f1497e Mon, Oct 24 2022 14:57:51.507

inptime: e700b5b6.1be67ba3 Mon, Oct 24 2022 14:56:54.108

*Oct 24 14:56:54:109 2022 交换机 NTP/7/ACL: -MDC=1; Access restrict: 0x00000008.

*Oct 24 14:56:54:109 2022 交换机 NTP/7/AUTH: -MDC=1; Received a packet at 39283, from 10.0.13.2, mode 4, key ID 00000000, length 48, authentication result 0

*Oct 24 14:56:54:109 2022 交换机 NTP/7/PARAM: -MDC=1; Clock filter param: number 8, offset 57.399556, delay 0.001907, dispersion 0.001935, jitter 0.008866, burst 0

*Oct 24 14:56:54:109 2022 交换机 NTP/7/SELECT: -MDC=1; peer 10.0.13.2, flash 0x00000800, flags 0x00000401, reach 255, root distance 0.011755

*Oct 24 14:56:54:109 2022 交换机 NTP/7/ADJUST: -MDC=1; Reset clock state, time count difference 67, state 1->1, poll 3, count 0, offset 0.000

规避措施：

经过本地环境验证，采用带源接口的措施可以规避该问题，相关命令：ntp-service unicast-server { server-name | ip-address }   source interface-type interface-number

源接口配置成直连的带ip的物理口或逻辑口。