The problems for update

erniu

When I first install ubuntu 6.10,I can update the system,but after I restart the system,when I type :sudo apt-get update,it indicate :can not connect to the server.even if I change a nother source.
attached sources list:
#deb http://ubuntu.csie.ntu.edu.tw/ubuntu/ edgy main restricted universe multiverse
#deb http://ubuntu.csie.ntu.edu.tw/ubuntu/ edgy-updates main restricted universe multiverse
#deb http://ubuntu.csie.ntu.edu.tw/ubuntu/ edgy-backports main restricted universe multiverse
#deb http://ubuntu.csie.ntu.edu.tw/ubuntu/ edgy-security main restricted universe multiverse
#deb http://ubuntu.csie.ntu.edu.tw/ubuntu/ edgy-proposed main multiverse restricted universe



deb http://ubuntu.cn99.com/ubuntu/ edgy main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu/ edgy-security main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu/ edgy-updates main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu/ edgy-proposed main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu/ edgy-backports main restricted universe multiverse
deb-src http://ubuntu.cn99.com/ubuntu/ edgy main restricted universe multiverse
deb-src http://ubuntu.cn99.com/ubuntu/ edgy-security main restricted universe multiverse
deb-src http://ubuntu.cn99.com/ubuntu/ edgy-updates main restricted universe multiverse
deb-src http://ubuntu.cn99.com/ubuntu/ edgy-proposed main restricted universe multiverse
deb-src http://ubuntu.cn99.com/ubuntu/ edgy-backports main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu-cn/ edgy main restricted universe multiverse
#deb http://security.ubuntu.com/ubuntu edgy main restricted universe multiverse
#deb http://security.ubuntu.com/ubuntu edgy-security main restricted universe multiverse
#deb http://security.ubuntu.com/ubuntu edgy-updates main restricted universe multiverse
#deb http://security.ubuntu.com/ubuntu edgy-proposed main restricted universe multiverse
#deb http://security.ubuntu.com/ubuntu edgy-backports main restricted universe multiverse
#deb-src http://security.ubuntu.com/ubuntu edgy main restricted universe multiverse
#deb-src http://security.ubuntu.com/ubuntu edgy-security main restricted universe multiverse
#deb-src http://security.ubuntu.com/ubuntu edgy-updates main restricted universe multiverse
#deb-src http://security.ubuntu.com/ubuntu edgy-proposed main restricted universe multiverse
#deb-src http://security.ubuntu.com/ubuntu edgy-backports main restricted universe multiverse

frankpzh

check your network connection first

erniu

现在更新服务器好像有问题，有时候连的上，有时候又连不上。