SDB:YOU: http/ftp Mirror Server Default Unsuitable / Slow Server

From openSUSE

Version: 8.2 -

Symptom

You want to use YOU to update your system via the Internet. After starting YOU, a selection list containing different mirror servers appears under 'Installation source'. You are not satisfied with the result. There are two basic problems that can arise here:

• The server proposed by YOU is very slow / is not working. When you select a different mirror server from the list, everything works.
• The server list proposed by YOU makes no sense. Servers are scattered around the world (USA, Australia, Japan, etc.), but there are no servers near your own location.

Cause

In order for YOU to define a suitable mirror server for your SUSE product, the SUSE Web server www.suse.de runs a small program that is queried by YOU in order to determine which mirror servers are available for the product you use.

The main information transmitted by YOU includes the product used, version numbers for important YOU components and the computer architecture. As of SUSE LINUX 9.0, the system also transmits additional information about the system time zone, as configured by you in YaST2.

Using the transmitted time zone and the product information, the system uses a list of possible http and ftp mirror servers around the world to create a list of mirror servers near you.

This list is made up of between 6 and 10 mirror servers which are mixed using a random function. They are then displayed in the YOU installation source selection window.

The SUSE Web server also checks at regular intervals to determine which mirror servers are still available. If the access fails, then the relevant mirror servers are removed from the list of possible mirror servers.

Solution

If a mirror server is not working properly, try one of the other possible mirror servers in the next YOU run. The list is deliberately mixed in order to spread the downloads as evenly as possible to ensure a satisfactory result in most cases.

If the mirror server selection list appears to be completely unsuitable, then you should check your time zone settings in YaST2 (provided you are using SUSE LINUX from version 9.0 and above). The default selections with "country" time zones such as "Europe/Berlin", "Europe/Paris" etc. work particularly well. If, for example, you set the US zone "GMT-7", then it is not possible to set a specific default. Instead, you should select "US/Mountain".

If the time zone transmitted by YOU to the SUSE Web server is unknown, or if you are using a version of SUSE LINUX before version 9.0, then the system will display German mirror servers first.

Why not "netselect" on the client?

Because that would require significant changes to YOU. It makes no sense to use netselect on the server.

In any case, a long RTT ping time does not necessarily mean a poor connection or a high load. In addition, ICMP echo and UDP would need to be released on the client side, which is often not the case, especially in company networks.

The mixing of options using the random generator is not perfect, but it provides customers with what is hopefully an even spread of possible mirror servers. In the past, the first server in the list (uni-kl) was hopelessly overloaded while the other servers were obviously completely "empty".

How exactly is the mirror list defined?

In the configuration file at www.suse.de, the (currently) approx. 30 mirror servers are saved with a text description and time zone. Using an extended /usr/share/zoneinfo/zone.tab file, the time zones are assigned to degrees of longitude/latitude to determine the distance of the YOU client from all the mirror servers on earth in order to determine the best 6 ~ 10 (minimum 6, more if the distance is the same as for the 6th mirror). After this, they are mixed using the random generator and returned to the client.