源自：http://stackoverflow.com/questions/27375137/failed-global-initialization-badvalue-invalid-or-no-user-locale-set-please-ens

Issue：

I run mongo I get the warning Failed global initialization: BadValue Invalid or no user locale set. Please ensure LANG and/or LC_* environment variables are set correctly.

Root Cause：

Looks like your locale settings are broken or non-existent on that VM, or at least that session on that VM. One of MongoDB's dependencies (boost) will fail when a locale is not correctly set (see SERVER-9032). For reference, before the change in SERVER-9032 this problem still happened but looked like this.

Sometimes logging out and back in can fix it (only broken for current session), or you can try running sudo local-gen to make sure generation is successful.

Resolution：

In the meantime, as a workaround to get mongo (or mongod etc.) running, just set your LC_ALL variable manually before starting the program:

export LC_ALL=C

mongo