git backup modify from http://sethrobertson.github.io/GitBestPractices/#backups

backupgit.sh

#!/bin/sh

GITHOST=scm@192.168.100.221
GITPATH=gitroot
cd ~/${GITPATH}_backup
ls -F . | grep / > /tmp/.gitmissing1
eval ssh -n $GITHOST ls -F ${GITPATH}/. | grep / > /tmp/.gitmissing2
diff /tmp/.gitmissing1 /tmp/.gitmissing2 | egrep '^>' |
  while read x f; do
      git clone --bare --mirror ${GITHOST}:${GITPATH}/$f $f
  done
rm -f /tmp/.gitmissing1 /tmp/.gitmissing2
for f in */.; do (cd $f; echo $f; git fetch); done