在FreeBSD系统上设置时间同步服务，可以按照以下步骤进行：
1、安装NTP软件包
需要在系统中安装NTP（Network Time Protocol）软件包，可以通过FreeBSD的包管理器pkg来安装，打开终端，输入以下命令：
“`
sudo pkg install ntp
“`
2、配置NTP服务器
安装完成后，需要配置NTP服务器，编辑/etc/ntp.conf文件，添加或修改以下内容：
“`
server your_ntp_server_ip_address
“`
将your_ntp_server_ip_address替换为你的NTP服务器IP地址，如果有多个NTP服务器，可以用空格分隔，
“`
server ntp1.example.com ntp2.example.com
“`
3、重启NTP服务
配置完成后，需要重启NTP服务以使更改生效，在终端中输入以下命令：
“`
sudo service ntp restart
“`
4、检查NTP同步状态
为了确保NTP服务正常运行并同步时间，可以检查其同步状态，在终端中输入以下命令：
“`
ntpq pn
“`
如果看到类似以下的输出，表示NTP服务正在运行并同步时间：
“`
remote refid st t when poll reach delay offset jitter
*LOCAL(0) 10.0.0.1 3 u 64 1 0.000 0.000 0.000 0.001
localhost 127.0.0.1 3 u 64 1 0.000 0.000 0.000 0.001
timea.google.com 172.217.194.59 3 u 64 1 1.855 2.597 1.855 0.368
timeb.google.com 172.217.234.59 3 u 64 1 1.855 2.597 1.855 0.368
timec.google.com 172.217.294.59 3 u 64 1 1.855 2.597 1.855 0.368
timed.google.com 172.217.334.59 3 u 64 1 1.855 2.597 1.855 0.368
timee.google.com 172.217.424.59 3 u 64 1 1.855 2.597 1.855 0.368
*REMOTE(O) timea.google.com refid st t when poll reach delay offset jitter
3 u 64 1 1.855 2.597 1.855 0.368
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
Reached, Local Clock is Faster than REMOTE by +2ms, Polling Server every 64s
===================================================
