linux clockdiff 命令介绍和使用案例
clockdiff 是一个用于测量本地主机与目标主机之间时间差的命令。它通过发送 ICMP 时间戳包来计算时间差，具有 1 毫秒的分辨率
clockdiff 命令介绍功能clockdiff 命令的主要功能是测量本地主机与指定目标主机之间的时间差。它可以帮助系统管理员了解网络延迟和时间同步的问题。
语法bashclockdiff [ -o ] [ -o1 ] destinationdestination: 要测量时间差的目标主机的 IP 地址或主机名。-o: 使用 IP 时间戳与 ICMP ECHO 替代 ICMP 时间戳消息。这对于某些不支持 ICMP 时间戳的目标主机（例如 Solaris <2.4）非常有用。-o1: 使用三项 IP 时间戳与预设跳地址，而不是四项。这种方式在某些目标主机上可能效果更好。注意事项一些节点（如 Cisco）可能使用非标准时间戳，这可能导致时间戳不准确。clockdiff 显示的时间差是以 24 天为周期的。该命令需要 CAP_NET_RAWIO 权限，通常需要 root 权限运行。命令安装部署：
root@meng:~# clockdiff
Command 'clockdiff' not found, but can be installed with:
apt install iputils-clockdiff
root@meng:~# which clockdiff
root@meng:~# apt install iputils-clockdiff
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
The following NEW packages will be installed:
iputils-clockdiff
0 upgraded, 1 newly installed, 0 to remove and 224 not upgraded.
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Get:1 http://mirrors.tuna.tsinghua.edu.cn/ubuntu jammy/universe amd64 iputils-clockdiff amd64 3:20211215-1 [12.8 kB]
Fetched 12.8 kB in 1s (14.7 kB/s)
Selecting previously unselected package iputils-clockdiff.
(Reading database ... 75119 files and directories currently installed.)
Preparing to unpack .../iputils-clockdiff_3%3a20211215-1_amd64.deb ...
Unpacking iputils-clockdiff (3:20211215-1) ...
Setting up iputils-clockdiff (3:20211215-1) ...
Processing triggers for man-db (2.10.2-1) ...
Scanning processes...
Scanning linux images...
Running kernel seems to be up-to-date.
No services need to be restarted.
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命令案例；
root@meng:~# clockdiff 192.168.10.20
clockdiff: 192.168.10.20 is down
root@meng:~# clockdiff 192.168.10.6
clockdiff: 192.168.10.6 time transmitted in a non-standard format
root@meng:~# clockdiff 192.168.10.16
..................................................
host=192.168.10.16 rtt=0(0)ms/0ms delta=0ms/0ms Mon Sep 2 11:09:16 2024
root@meng:~# clockdiff -o1 192.168.10.16
..................................................
host=192.168.10.16 rtt=0(0)ms/0ms delta=0ms/0ms Mon Sep 2 11:09:29 2024
root@meng:~# clockdiff -o1 192.168.10.6
clockdiff: 192.168.10.6 is down
root@meng:~# clockdiff -o1 192.168.10.20
.................................clockdiff: 192.168.10.20 is down
root@meng:~#
