ubuntu服务器安装libapache2-mod-php5时报错

ubuntu服务器安装libapache2-mod-php5时报错，请大神帮忙看看 怎么回事，是网络问题吗？在线急等
root@iZ28q902yy9Z:/etc# apt-get install libapache2-mod-php5
Reading package lists... Done
Building dependency tree      
Reading state information... Done
The following extra packages will be installed:
  php5-cli php5-common php5-json php5-readline
Suggested packages:
  php-pear php5-user-cache
The following NEW packages will be installed:
  libapache2-mod-php5 php5-cli php5-common php5-json php5-readline
0 upgraded, 5 newly installed, 0 to remove and 127 not upgraded.
Need to get 4,824 kB/4,858 kB of archives.
After this operation, 20.4 MB of additional disk space will be used.
Do you want to continue? [Y/n] y
Err http:/mirrors.aliyun.com/ubuntu/ trusty-proposed/main php5-common amd64 5.5.9+dfsg-1ubuntu4.12
  404  Not Found [IP: 115.28.122.210 80]
Err http:/mirrors.aliyuncs.com/ubuntu/ trusty-proposed/main php5-common amd64 5.5.9+dfsg-1ubuntu4.12
  404  Not Found
Err http:/mirrors.aliyuncs.com/ubuntu/ trusty-proposed/main php5-cli amd64 5.5.9+dfsg-1ubuntu4.12
  404  Not Found
Err http:/mirrors.aliyuncs.com/ubuntu/ trusty-proposed/main php5-readline amd64 5.5.9+dfsg-1ubuntu4.12
  404  Not Found
Err http:/mirrors.aliyuncs.com/ubuntu/ trusty-proposed/main libapache2-mod-php5 amd64 5.5.9+dfsg-1ubuntu4.12
  404  Not Found
E: Failed to fetch http:/mirrors.aliyuncs.com/ubuntu/pool/main/p/php5/php5-common_5.5.9+dfsg-1ubuntu4.12_amd64.deb  404  Not Found


E: Failed to fetch http:/mirrors.aliyuncs.com/ubuntu/pool/main/p/php5/php5-cli_5.5.9+dfsg-1ubuntu4.12_amd64.deb  404  Not Found


E: Failed to fetch http:/mirrors.aliyuncs.com/ubuntu/pool/main/p/php5/php5-readline_5.5.9+dfsg-1ubuntu4.12_amd64.deb  404  Not Found


E: Failed to fetch http:/mirrors.aliyuncs.com/ubuntu/pool/main/p/php5/libapache2-mod-php5_5.5.9+dfsg-1ubuntu4.12_amd64.deb  404  Not Found


E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?