Unix-commands-clockdiff
提供:Dev Guides
clockdiff-Unix、Linuxコマンド
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NAME
概要
説明
パケット、またはオプションでIP TIMESTAMPオプション
ICMP ECHOにオプションが追加されました。
Tag | Description |
---|---|
-o | Use IP TIMESTAMP with ICMP ECHO instead of ICMP TIMESTAMP messages. It is useful with some destinations, which do not support ICMP TIMESTAMP (f.e. Solaris <2.4). |
*-o1 * | Slightly different form of* -o*, namely it uses three-term IP TIMESTAMP with prespecified hop addresses instead of four term one. What flavor works better depends on target host. Particularly, *-o *is better for Linux. |
警告
Tag | Description |
---|---|
o | Some nodes (Cisco) use non-standard timestamps, which is allowed by RFC, but makes timestamps mostly useless. |
o | Some nodes generate messed timestamps (Solaris>2.4), when run* xntpd*. Seems, its IP stack uses a corrupted clock source, which is synchronized to time-of-day clock periodically and jumps randomly making timestamps mostly useless. Good news is that you can use NTP in this case, which is even better. |
o | clockdiff shows difference in time modulo 24 days. |
関連項目
参考文献
[1] ICMP ECHO, RFC0792、14ページ。
[2] ICMP TIMESTAMP, RFC0792、16ページ。
[3] IP TIMESTAMP option, RFC0791、3.1、16ページ。
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