在aws ami-baba68d3上的Ubuntu 11.10上,apt-get install build-essentials失败了

我试图在ubuntu服务器上安装和配置Xabbix.遵循维基上的说明,第一步失败：

sudo apt-get install build-essential

我收到以下错误消息：

Err http://us-east-1.ec2.archive.ubuntu.com/ubuntu/ oneiric-updates/main linux-libc-dev amd64 3.0.0-16.28
404  Not Found [IP: 10.252.111.96 80]
Err http://security.ubuntu.com/ubuntu/ oneiric-security/main linux-libc-dev amd64 3.0.0-16.28
404  Not Found [IP: 91.189.92.166 80]
Failed to fetch http://security.ubuntu.com/ubuntu/pool/main/l/linux/linux-libc-dev_3.0.0-16.28_amd64.deb  404  Not Found [IP: 91.189.92.166 80]
E: Unable to fetch some archives,maybe run apt-get update or try with --fix-missing

我试过建议–fix-missing.那里没有运气.

我跑了：
apt-get update

然后我就能运行build-essential安装了.