H3C Technologies H3C S7500E Series Switches - Manual (Page 96)

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Configuring MPLS VPN Time Synchronization in Symmetric Peers Mode
Network requirements
As shown in Figure 3-13, two VPNs are present on PE 1 and PE 2: VPN 1 and VPN 2. To
synchronize the time between PE 1 and PE 2 in VPN 1, perform the following configurations:
z PE 1’s local clock is to be used as a reference source, with the stratum level of 1.
z PE 2 is synchronized to PE 1 in the symmetric peers mode, and specify that the VPN
instance is VPN 1.
Configuration procedure
1) Configure IP addresses for interfaces (omitted).
2) Configuration on PE 1:
# Specify the local clock as the reference source, with the stratum level of 1.
system-view
[PE1] ntp-service refclock-master 1
3) Configuration on PE 2:
# Specify PE 1 in VPN 1 as the symmetric-passive peer of PE 2.
system-view
[PE2] ntp-service unicast-peer vpn-instance vpn1 10.1.1.2
# View the NTP session information and status information on PE 2 a certain period of time later.
The information should show that PE 2 has been synchronized to PE 1, with the clock stratum
level of 2.
[PE2] display ntp-service status
Clock status: synchronized
Clock stratum: 2
Reference clock ID: 10.1.1.2
Nominal frequency: 99.9100 Hz
Actual frequency: 99.9100 Hz
Clock precision: 2^18
Clock offset: 0.0000 ms
Root delay: 32.00 ms
Root dispersion: 0.60 ms
Peer dispersion: 7.81 ms
Reference time: 02:44:01.200 UTC Jan 1 2001(BDFA6D71.33333333)
[PE2] display ntp-service sessions
source reference stra reach poll now offset delay disper
**************************************************************************
[12345]10.1.1.2 LOCL 1 1 64 29 -12.0 32.0 15.6
note: 1 source(master),2 source(peer),3 selected,4 candidate,5 configured
Total associations : 1
[PE2] display ntp-service trace
server 127.0.0.1,stratum 2, offset -0.012000, synch distance 0.02448
server 10.1.1.2,stratum 1, offset 0.003500, synch distance 0.00781
refid 127.127.1.0