problems of using git to fetch EMC2

I did follow the steps of fetching EMC2 with git, but some of the timeout problems occured~~

first install git, then
root@vc-desktop:~# git clone git://git.linuxcnc.org/git/emc2.git emc2-dev
Initialized empty Git repository in /root/emc2-dev/.git/
git.linuxcnc.org[0: 76.79.58.172]: errno=Connection timed out
fatal: unable to connect a socket (Connection timed out)
fetch-pack from 'git://git.linuxcnc.org/git/emc2.git' failed.

is it because of the network problems???
besides, I tried to use the proxy, and tried again, but failed one more time~~!!