Ubuntu apt-get failed to fetch packages
<p>I use ubuntu 14.04. apt-get worked fine until recently. apt-get will return failure message while using <code>apt-get update</code>:</p>

<pre><code>    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty/Release.gpg  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-updates/Release.gpg  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-backports/Release.gpg  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-security/Release.gpg  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty/main/source/Sources  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty/restricted/source/Sources  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty/universe/source/Sources  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty/multiverse/source/Sources  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty/main/binary-amd64/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty/restricted/binary-amd64/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty/universe/binary-amd64/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty/multiverse/binary-amd64/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty/main/binary-i386/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty/restricted/binary-i386/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty/universe/binary-i386/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty/multiverse/binary-i386/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty/main/i18n/Translation-en_US  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty/main/i18n/Translation-en  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty/multiverse/i18n/Translation-en_US  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty/multiverse/i18n/Translation-en  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty/restricted/i18n/Translation-en_US  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty/restricted/i18n/Translation-en  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty/universe/i18n/Translation-en_US  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty/universe/i18n/Translation-en  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-updates/main/source/Sources  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-updates/restricted/source/Sources  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-updates/universe/source/Sources  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-updates/multiverse/source/Sources  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-updates/main/binary-amd64/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-updates/restricted/binary-amd64/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-updates/universe/binary-amd64/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-updates/multiverse/binary-amd64/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-updates/main/binary-i386/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-updates/restricted/binary-i386/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-updates/universe/binary-i386/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-updates/multiverse/binary-i386/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-updates/main/i18n/Translation-en_US  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-updates/main/i18n/Translation-en  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-updates/multiverse/i18n/Translation-en_US  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-updates/multiverse/i18n/Translation-en  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-updates/restricted/i18n/Translation-en_US  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-updates/restricted/i18n/Translation-en  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-updates/universe/i18n/Translation-en_US  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-updates/universe/i18n/Translation-en  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-backports/main/source/Sources  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-backports/restricted/source/Sources  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-backports/universe/source/Sources  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-backports/multiverse/source/Sources  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-backports/main/binary-amd64/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-backports/restricted/binary-amd64/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-backports/universe/binary-amd64/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-backports/multiverse/binary-amd64/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-backports/main/binary-i386/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-backports/restricted/binary-i386/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-backports/universe/binary-i386/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-backports/multiverse/binary-i386/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-backports/main/i18n/Translation-en_US  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-backports/main/i18n/Translation-en  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-backports/multiverse/i18n/Translation-en_US  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-backports/multiverse/i18n/Translation-en  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-backports/restricted/i18n/Translation-en_US  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-backports/restricted/i18n/Translation-en  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-backports/universe/i18n/Translation-en_US  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-backports/universe/i18n/Translation-en  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-security/main/source/Sources  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-security/restricted/source/Sources  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-security/universe/source/Sources  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-security/multiverse/source/Sources  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-security/main/binary-amd64/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-security/restricted/binary-amd64/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-security/universe/binary-amd64/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-security/multiverse/binary-amd64/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-security/main/binary-i386/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-security/restricted/binary-i386/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-security/universe/binary-i386/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-security/multiverse/binary-i386/Packages  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-security/main/i18n/Translation-en_US  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-security/main/i18n/Translation-en  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-security/multiverse/i18n/Translation-en_US  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-security/multiverse/i18n/Translation-en  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-security/restricted/i18n/Translation-en_US  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-security/restricted/i18n/Translation-en  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-security/universe/i18n/Translation-en_US  Connection failed [IP: 115.28.122.210 80]
    Failed to fetch http://mirrors.aliyun.com/ubuntu/dists/trusty-security/universe/i18n/Translation-en  Connection failed [IP: 115.28.122.210 80]
    Some index files failed to download. They have been ignored, or old ones used instead.
</code></pre>

<p>I tried to change source to mirrors.163.com or main server. It still failed.
Ping those server shows the connection is OK:</p>

<pre><code>    $ ping mirrors.aliyun.com
    PING mirrors.aliyun.com (112.124.140.210) 56(84) bytes of data.
    64 bytes from 112.124.140.210: icmp_seq=1 ttl=54 time=12.5 ms
    64 bytes from 112.124.140.210: icmp_seq=2 ttl=54 time=12.2 ms
    64 bytes from 112.124.140.210: icmp_seq=3 ttl=54 time=13.5 ms
</code></pre>

<p>Does anyone know how to solve this? Thanks</p>