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New Installer: NTP
One possibility is to select NTP servers from a static list depending on the country setting gathered from IP information. This approach faces several problems:
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A static list must be maintained and always faces a risk of being outdated. For an example see bug #458917.
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Use of the data is legally difficult. E.g. "Usage Guidelines" even for "Open Access" includes:
"Time Server DNS addresses should not be hard-coded in any hardware, firmware, or software without advance explicit written permission from the time server operator."
http://support.ntp.org/bin/view/Servers/StratumTwoTimeServers
The static list could be downloaded during configuration so that we can update it during the long life-time of SLE but it still needs to be maintained.
Using NTP Pool (http://www.pool.ntp.org/) has several advantages.
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Offers pools for continental zones (e.g. Europe) and countries (e.g. Germany). But some countries have only a few servers, e.g. New Caledonia.
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Offers pools for vendors, http://www.pool.ntp.org/en/vendors.html.
The pool {0-3}.opensuse.pool.ntp.org already exists.
"If you are a commercial / closed-source vendor we will ask for a small contribution to help scaling the pool to meet demands."
For SLE we could be required (legally or ethically) to create a separate zone and provide a contribution.
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The NTP Pool DNS system automatically picks time servers which are geographically close for you.
http://support.ntp.org/bin/view/Servers/NTPPoolServers
Anyway, {0-3}.de.pool.ntp.org seems to be faster than {0-3}.opensuse.pool.ntp.org or even {0-3}.nc.pool.ntp.org (using ping).
Locate NTP servers via SLP.
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Likely nearest and trusted server.
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Problematic for notebooks as the servers can become unreachable when system is moved.
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Per default use product specific vendor NTP Pool.
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For immobile systems locate NTP servers via SLP. If that fails offer to use country or continental pool depending on number of available servers.
This requires a static list for countries with enough servers. Maintaining this list should not be much work.
The decision between vendor or country pool could be provided by the product, role and hardware. Hwinfo (libhd) reports form factor for the computer, it can detect a laptop. And for example SLES on S/390 is immobile.
- Are there security concerns?