NTP H3C device clock can not synchronize investigation methods

NTP clock can not be synchronized troubleshooting methods:
1, V5 equipment NTP synchronized version of the default V3 version, V7 Default is V4 version, if you configure NTP directly on the V7 device, the clock on the NTP may not be able to synchronize, you need to manually release change the clock can be synchronized V3
V5 equipment to check the version as follows:
[H3C] ntp DIS Sessions ver
[H3C] ntp DIS Sessions verbose
clock Source: 10.1.12.1
clock a Stratum: 2
clock Status: the Configured, Master, SANE,! Valid
Reference clock ID: 127.127.1.0
local the MODE: the Active, local poll: 6
the peer the MODE: passive, the peer poll: 6
offset: -455.5000 MS, Delay: MS 15.00, Disper: 16.90 MS
root Delay: MS 0.00, root Disper: 34.29 MS
the REACH : 255, Sync dist: 0.381, Sync State:. 5
Precision: 2 ^. 7, Version:. 3, Use the peer interface: wildcard
reftime:. 11:. 19: 45.885 24-Nov 2016 UTC (DBE14B51.E28F5C28)
orgtime: 11:20:24.027 UTC Nov 24 2016(DBE14B78.06E978D4)
rcvtime: 11:20:24.490 UTC Nov 24 2016(DBE14B78.7D70A3D7)
xmttime: 11:20:24.475 UTC Nov 24 2016(DBE14B78.79999999)
filter delay : 0.02 0.02 0.02 0.02 0.02 0.03 0.03 0.01
filter offset: -0.46 0.00 0.00 0.00 0.00 -0.46 -0.46 -0.46
filter disper: 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02
Total associations : 1
V7设备查看版本如下：
[H3C]dis ntp-service sessions verbose
Clock source: 10.1.12.1
Session ID: 15127
Clock stratum: 2
Clock status: configured, candidate, sane, valid
Reference clock ID: 127.127.1.0
instance: Not specified
Local mode: sym_active, local poll interval: 6
Peer mode: sym_passive, peer poll interval: 6
Offset: -4.465ms, roundtrip delay: 0.4425ms, dispersion: 0.1373ms
Root roundtrip delay: 0.0000ms, root dispersion: 11.825ms
Reachabilities:3, sync distance: 0.0144
Precision: 2^-15, version: 4, source interface: Not specified
Reftime: dbe0fad3.88ccf3f1 Thu, Nov 24 2016 5:36:19.534
Orgtime: dbe0fb0c.4ece8e83 Thu, Nov 24 2016 5:37:16.307
Rcvtime: dbe0fb0c.4d362302 Thu, Nov 24 2016 5:37:16.301
Xmttime: dbe0fb0c.4d362302 Thu, Nov 24 2016 5:37:16.301
Roundtrip delay samples: 1.068 0.930 0.656 1.129 0.442 0.000 0.000 0.000
Offset samples: -6.85 -7.61 -3.89 -3.16 -4.47 0.00 0.00 0.00
Filter order: 4 2 1 0 3 5 6 7
Use the peer-Service-unicast-NTP 10.1.12.1. 3 Version
2, V7 need to change the clock mode protocol NTP
[H3C] Clock NTP Protocol
. 3, can not be synchronized if, when the source synchronous interfaces specified NTP
[H3C] ntp unicast-server 100.1 .12.1 source g0 / 1