i had succeeded to download the boundaries from the website https://osm.wno-edv-service.de/boundaries/’ a month ago.but now it can’t work.can anyone tell me how can i download boundaries ?thanks!
Even if you manage to download the the boundary, it will not be the official boundary. As well as mapping errors, OSM tends to follow a policy of what is on the ground, so is likely to represent disputed territory as belonging to the country that currently has defacto control. More details are in https://wiki.osmfoundation.org/w/images/d/d8/DisputedTerritoriesInformation.pdf
In particular, I believe the current situation is that the government of the People’s Republic of China considers the island of Taiwan to be within the boundaries of China, but, as they do not have control there, that is not how it will be represented in OSM.
If all else fails, you can download the relation http://www.openstreetmap.org/relation/270056 using the API, and including all the included relations, then delete all the segments of ways that are duplicated. You might want to look at the source code of the web site, as I presume that has to do this in order to present the border when you use the above URL.
thanks! i get it.