# 

#deb      http://mirror.cc.columbia.edu/debian/       buster          main  non-free  contrib
#deb-src  http://mirror.cc.columbia.edu/debian/       buster          main  non-free  contrib
deb       http://ftp.us.debian.org/debian/            buster          main  non-free  contrib
deb-src   http://ftp.us.debian.org/debian/            buster          main  non-free  contrib
deb       http://security.debian.org/debian-security  buster/updates  main  contrib   non-free
deb-src   http://security.debian.org/debian-security  buster/updates  main  contrib   non-free

# updates, previously known as 'volatile'
deb       http://ftp.us.debian.org/debian/       buster-updates  main  contrib  non-free
deb-src   http://ftp.us.debian.org/debian/       buster-updates  main  contrib  non-free
#deb      http://mirror.cc.columbia.edu/debian/  stretch-updates  main  contrib  non-free
#deb-src  http://mirror.cc.columbia.edu/debian/  stretch-updates  main  contrib  non-free

# backports, previously on backports.debian.org
#deb      http://mirror.cc.columbia.edu/debian/  stretch-backports  main  contrib  non-free
#deb-src  http://mirror.cc.columbia.edu/debian/  stretch-backports  main  contrib  non-free