Cable Modem Troubleshooting Tips


Time Synchronisation

When sending e-mails or posting news, the PC's clock will be used to timestamp the message. It is therefore helpful to others if your PC's date and time are kept correct. This can be done manually, and/or with automatic assistance

The best way of automatically synchronising computer clocks is to use the Network Time Protocol (NTP, sometimes known as SNTP, not to be confused with NNTP or SMTP) on port 123. The NTP system is capable of synchronising computer clocks with an accuracy of a few scores of microseconds. To use NTP you need to:

Typical places to try for an NTP server are (use the first of this list that works for you, on the principle of using the closest NTP server possible):

For all Windows users, first ensure that the PC is in the correct timezone, and set the time manually:

Windows 9x/ME/NT: For automatic synchronisation, some popular time clients (e.g. WorldTime, TimeSync) do not support the NTP protocol. The following freeware applications support NTP synchronisation:

Set up AboutTime as follows:

Windows 2000 has an NTP client built-in, a very smart one which not only synchronises your clock but also tweaks the rate of the clock so that it keeps better time anyway. If the Windows Time service is not already started, set it up as follows:

This setup will automatically start the time synchroniser after every restart. If the Windows Time service had already been started, then just use the following commands:

net stop  "Windows Time"
net time  /
net start "Windows Time"

where is the DNS name or IP number of the new NTP server. [Thanks to NiShFiSh for this Windows 2000 information].

Windows XP supports network time synchronisation. As installed, it synchronises automatically to a Microsoft time server in the USA. To select a closer time server:

This simple XP service synchronises with the server only once a week.

Apple Mac OS 8.5 to 9.2: has an NTP client incorporated into the Date & Time control panel. Set it up as follows:

Apple Mac OS X:

Linux users should create or edit the file /etc/ntp.conf to contain the line:


where is the NTP server address that you discovered. Starting the NTP client daemon varies according to system: for RedHat 7.0 give the command:

chkconfig --level 345 ntpd on

RedHat 6.2 uses xntpd instead of ntpd. [Thanks to Jon Peatfield for this Linux information].

Other platforms: see

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