阿里云无法安装svn，提示Could not resolve host
最近，在阿里云的一台机子安装svn时，提示"Could not resolve host: mirrors.cloud.aliyuncs.com; Unknown error"。
# yum install -y subversion
Loaded plugins: fastestmirror
http://mirrors.cloud.aliyuncs.com/centos/7/os/x86_64/repodata/repomd.xml: [Errno 14] curl#6 - "Could not resolve host: mirrors.cloud.aliyuncs.com; Unknown error"
Trying other mirror.
http://mirrors.cloud.aliyuncs.com/epel/7/x86_64/repodata/repomd.xml: [Errno 14] curl#6 - "Could not resolve host: mirrors.cloud.aliyuncs.com; Unknown error"
Trying other mirror.
http://mirrors.cloud.aliyuncs.com/centos/7/extras/x86_64/repodata/repomd.xml: [Errno 14] curl#6 - "Could not resolve host: mirrors.cloud.aliyuncs.com; Unknown error"
Trying other mirror.
http://mirrors.cloud.aliyuncs.com/centos/7/updates/x86_64/repodata/repomd.xml: [Errno 14] curl#6 - "Could not resolve host: mirrors.cloud.aliyuncs.com; Unknown error"
Trying other mirror.
Loading mirror speeds from cached hostfile
Resolving Dependencies
--> Running transaction check
---> Package subversion.x86_64 0:1.7.14-14.el7 will be installed
--> Processing Dependency: subversion-libs(x86-64) = 1.7.14-14.el7 for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_wc-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_subr-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_repos-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_ra_svn-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_ra_neon-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_ra_local-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_ra-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_fs_util-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_fs_fs-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_fs_base-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_fs-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_diff-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_delta-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_client-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libneon.so.27()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libaprutil-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libapr-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Running transaction check
---> Package apr.x86_64 0:1.4.8-3.el7_4.1 will be installed
---> Package apr-util.x86_64 0:1.5.2-6.el7 will be installed
---> Package neon.x86_64 0:0.30.0-3.el7 will be installed
--> Processing Dependency: libgnutls.so.28(GNUTLS_2_12)(64bit) for package: neon-0.30.0-3.el7.x86_64
--> Processing Dependency: libgnutls.so.28(GNUTLS_1_4)(64bit) for package: neon-0.30.0-3.el7.x86_64
--> Processing Dependency: libproxy.so.1()(64bit) for package: neon-0.30.0-3.el7.x86_64
--> Processing Dependency: libpakchois.so.0()(64bit) for package: neon-0.30.0-3.el7.x86_64
--> Processing Dependency: libgnutls.so.28()(64bit) for package: neon-0.30.0-3.el7.x86_64
---> Package subversion-libs.x86_64 0:1.7.14-14.el7 will be installed
--> Running transaction check
---> Package gnutls.x86_64 0:3.3.26-9.el7 will be installed
--> Processing Dependency: trousers >= 0.3.11.2 for package: gnutls-3.3.26-9.el7.x86_64
--> Processing Dependency: libnettle.so.4()(64bit) for package: gnutls-3.3.26-9.el7.x86_64
--> Processing Dependency: libhogweed.so.2()(64bit) for package: gnutls-3.3.26-9.el7.x86_64
---> Package libproxy.x86_64 0:0.4.11-11.el7 will be installed
--> Processing Dependency: libmodman.so.1()(64bit) for package: libproxy-0.4.11-11.el7.x86_64
---> Package pakchois.x86_64 0:0.4-10.el7 will be installed
--> Running transaction check
---> Package libmodman.x86_64 0:2.0.1-8.el7 will be installed
---> Package nettle.x86_64 0:2.7.1-8.el7 will be installed
---> Package trousers.x86_64 0:0.3.14-2.el7 will be installed
--> Finished Dependency Resolution
Dependencies Resolved
====================================================================================================================
Package Arch Version Repository Size
====================================================================================================================
Installing:
subversion x86_64 1.7.14-14.el7 base 1.0 M
Installing for dependencies:
apr x86_64 1.4.8-3.el7_4.1 base 103 k
apr-util x86_64 1.5.2-6.el7 base 92 k
gnutls x86_64 3.3.26-9.el7 base 677 k
libmodman x86_64 2.0.1-8.el7 base 28 k
libproxy x86_64 0.4.11-11.el7 base 64 k
neon x86_64 0.30.0-3.el7 base 165 k
nettle x86_64 2.7.1-8.el7 base 327 k
pakchois x86_64 0.4-10.el7 base 14 k
subversion-libs x86_64 1.7.14-14.el7 base 922 k
trousers x86_64 0.3.14-2.el7 base 289 k
Transaction Summary
====================================================================================================================
Install 1 Package (+10 Dependent packages)
Total download size: 3.6 M
Installed size: 12 M
Downloading packages:
Delta RPMs disabled because /usr/bin/applydeltarpm not installed.
apr-1.4.8-3.el7_4.1.x86_64.rpm FAILED
http://mirrors.cloud.aliyuncs.com/centos/7/os/x86_64/Packages/apr-1.4.8-3.el7_4.1.x86_64.rpm: [Errno 14] curl#6 - "Could not resolve host: mirrors.cloud.aliyuncs.com; Unknown error"
Trying other mirror.
apr-util-1.5.2-6.el7.x86_64.rp FAILED
http://mirrors.cloud.aliyuncs.com/centos/7/os/x86_64/Packages/apr-util-1.5.2-6.el7.x86_64.rpm: [Errno 14] curl#6 - "Could not resolve host: mirrors.cloud.aliyuncs.com; Unknown error"
Trying other mirror.
gnutls-3.3.26-9.el7.x86_64.rpm FAILED
http://mirrors.cloud.aliyuncs.com/centos/7/os/x86_64/Packages/gnutls-3.3.26-9.el7.x86_64.rpm: [Errno 14] curl#6 - "Could not resolve host: mirrors.cloud.aliyuncs.com; Unknown error"
Trying other mirror.
libmodman-2.0.1-8.el7.x86_64.r FAILED
http://mirrors.cloud.aliyuncs.com/centos/7/os/x86_64/Packages/libmodman-2.0.1-8.el7.x86_64.rpm: [Errno 14] curl#6 - "Could not resolve host: mirrors.cloud.aliyuncs.com; Unknown error"
Trying other mirror.
libproxy-0.4.11-11.el7.x86_64. FAILED
http://mirrors.cloud.aliyuncs.com/centos/7/os/x86_64/Packages/libproxy-0.4.11-11.el7.x86_64.rpm: [Errno 14] curl#6 - "Could not resolve host: mirrors.cloud.aliyuncs.com; Unknown error"
Trying other mirror.
neon-0.30.0-3.el7.x86_64.rpm FAILED
http://mirrors.cloud.aliyuncs.com/centos/7/os/x86_64/Packages/neon-0.30.0-3.el7.x86_64.rpm: [Errno 14] curl#6 - "Could not resolve host: mirrors.cloud.aliyuncs.com; Unknown error"
Trying other mirror.
nettle-2.7.1-8.el7.x86_64.rpm FAILED
http://mirrors.cloud.aliyuncs.com/centos/7/os/x86_64/Packages/nettle-2.7.1-8.el7.x86_64.rpm: [Errno 14] curl#6 - "Could not resolve host: mirrors.cloud.aliyuncs.com; Unknown error"
Trying other mirror.
pakchois-0.4-10.el7.x86_64.rpm FAILED
http://mirrors.cloud.aliyuncs.com/centos/7/os/x86_64/Packages/pakchois-0.4-10.el7.x86_64.rpm: [Errno 14] curl#6 - "Could not resolve host: mirrors.cloud.aliyuncs.com; Unknown error"
Trying other mirror.
subversion-1.7.14-14.el7.x86_6 FAILED
http://mirrors.cloud.aliyuncs.com/centos/7/os/x86_64/Packages/subversion-1.7.14-14.el7.x86_64.rpm: [Errno 14] curl#6 - "Could not resolve host: mirrors.cloud.aliyuncs.com; Unknown error"
Trying other mirror.
subversion-libs-1.7.14-14.el7. FAILED
http://mirrors.cloud.aliyuncs.com/centos/7/os/x86_64/Packages/subversion-libs-1.7.14-14.el7.x86_64.rpm: [Errno 14] curl#6 - "Could not resolve host: mirrors.cloud.aliyuncs.com; Unknown error"
Trying other mirror.
trousers-0.3.14-2.el7.x86_64.r FAILED
http://mirrors.cloud.aliyuncs.com/centos/7/os/x86_64/Packages/trousers-0.3.14-2.el7.x86_64.rpm: [Errno 14] curl#6 - "Could not resolve host: mirrors.cloud.aliyuncs.com; Unknown error"
Trying other mirror.
Error downloading packages:
neon-0.30.0-3.el7.x86_64: [Errno 256] No more mirrors to try.
trousers-0.3.14-2.el7.x86_64: [Errno 256] No more mirrors to try.
libmodman-2.0.1-8.el7.x86_64: [Errno 256] No more mirrors to try.
subversion-1.7.14-14.el7.x86_64: [Errno 256] No more mirrors to try.
libproxy-0.4.11-11.el7.x86_64: [Errno 256] No more mirrors to try.
pakchois-0.4-10.el7.x86_64: [Errno 256] No more mirrors to try.
apr-1.4.8-3.el7_4.1.x86_64: [Errno 256] No more mirrors to try.
nettle-2.7.1-8.el7.x86_64: [Errno 256] No more mirrors to try.
gnutls-3.3.26-9.el7.x86_64: [Errno 256] No more mirrors to try.
apr-util-1.5.2-6.el7.x86_64: [Errno 256] No more mirrors to try.
subversion-libs-1.7.14-14.el7.x86_64: [Errno 256] No more mirrors to try.经过查询资料得知，mirrors.cloud.aliyuncs.com是阿里云ECS VPC 用户专用的镜像源域名。
那不能说停就停吧？如果停了对阿里云上所有的ECS应该都会有很大影响。
然后换了另外一台阿里云的机器测试，发现另一台服务也是用的这个镜像源域名，但是却使用正常。
再排查机器配置，发现DNS不一样
问题机器的DNS是223.5.5.5和223.6.6.6
正常机器的DNS是100.100.2.136和100.100.2.138
最后修改DNS为正常机器的
# cat /etc/resolv.conf
nameserver 100.100.2.136
nameserver 100.100.2.138再重新执行安装，就正常安装了
# yum install -y subversion
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
Resolving Dependencies
--> Running transaction check
---> Package subversion.x86_64 0:1.7.14-14.el7 will be installed
--> Processing Dependency: subversion-libs(x86-64) = 1.7.14-14.el7 for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_wc-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_subr-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_repos-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_ra_svn-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_ra_neon-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_ra_local-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_ra-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_fs_util-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_fs_fs-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_fs_base-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_fs-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_diff-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_delta-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libsvn_client-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libneon.so.27()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libaprutil-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Processing Dependency: libapr-1.so.0()(64bit) for package: subversion-1.7.14-14.el7.x86_64
--> Running transaction check
---> Package apr.x86_64 0:1.4.8-3.el7_4.1 will be installed
---> Package apr-util.x86_64 0:1.5.2-6.el7 will be installed
---> Package neon.x86_64 0:0.30.0-3.el7 will be installed
--> Processing Dependency: libgnutls.so.28(GNUTLS_2_12)(64bit) for package: neon-0.30.0-3.el7.x86_64
--> Processing Dependency: libgnutls.so.28(GNUTLS_1_4)(64bit) for package: neon-0.30.0-3.el7.x86_64
--> Processing Dependency: libproxy.so.1()(64bit) for package: neon-0.30.0-3.el7.x86_64
--> Processing Dependency: libpakchois.so.0()(64bit) for package: neon-0.30.0-3.el7.x86_64
--> Processing Dependency: libgnutls.so.28()(64bit) for package: neon-0.30.0-3.el7.x86_64
---> Package subversion-libs.x86_64 0:1.7.14-14.el7 will be installed
--> Running transaction check
---> Package gnutls.x86_64 0:3.3.29-9.el7_6 will be installed
--> Processing Dependency: trousers >= 0.3.11.2 for package: gnutls-3.3.29-9.el7_6.x86_64
--> Processing Dependency: libnettle.so.4()(64bit) for package: gnutls-3.3.29-9.el7_6.x86_64
--> Processing Dependency: libhogweed.so.2()(64bit) for package: gnutls-3.3.29-9.el7_6.x86_64
---> Package libproxy.x86_64 0:0.4.11-11.el7 will be installed
--> Processing Dependency: libmodman.so.1()(64bit) for package: libproxy-0.4.11-11.el7.x86_64
---> Package pakchois.x86_64 0:0.4-10.el7 will be installed
--> Running transaction check
---> Package libmodman.x86_64 0:2.0.1-8.el7 will be installed
---> Package nettle.x86_64 0:2.7.1-8.el7 will be installed
---> Package trousers.x86_64 0:0.3.14-2.el7 will be installed
--> Finished Dependency Resolution
Dependencies Resolved
===============================================================================================================================================================
Package Arch Version Repository Size
===============================================================================================================================================================
Installing:
subversion x86_64 1.7.14-14.el7 base 1.0 M
Installing for dependencies:
apr x86_64 1.4.8-3.el7_4.1 base 103 k
apr-util x86_64 1.5.2-6.el7 base 92 k
gnutls x86_64 3.3.29-9.el7_6 updates 680 k
libmodman x86_64 2.0.1-8.el7 base 28 k
libproxy x86_64 0.4.11-11.el7 base 64 k
neon x86_64 0.30.0-3.el7 base 165 k
nettle x86_64 2.7.1-8.el7 base 327 k
pakchois x86_64 0.4-10.el7 base 14 k
subversion-libs x86_64 1.7.14-14.el7 base 922 k
trousers x86_64 0.3.14-2.el7 base 289 k
Transaction Summary
===============================================================================================================================================================
Install 1 Package (+10 Dependent packages)
Total download size: 3.6 M
Installed size: 12 M
Downloading packages:
(1/11): apr-1.4.8-3.el7_4.1.x86_64.rpm | 103 kB 00:00:00
(2/11): libmodman-2.0.1-8.el7.x86_64.rpm | 28 kB 00:00:00
(3/11): libproxy-0.4.11-11.el7.x86_64.rpm | 64 kB 00:00:00
(4/11): apr-util-1.5.2-6.el7.x86_64.rpm | 92 kB 00:00:00
(5/11): neon-0.30.0-3.el7.x86_64.rpm | 165 kB 00:00:00
(6/11): nettle-2.7.1-8.el7.x86_64.rpm | 327 kB 00:00:00
(7/11): pakchois-0.4-10.el7.x86_64.rpm | 14 kB 00:00:00
(8/11): gnutls-3.3.29-9.el7_6.x86_64.rpm | 680 kB 00:00:00
(9/11): subversion-1.7.14-14.el7.x86_64.rpm | 1.0 MB 00:00:00
(10/11): trousers-0.3.14-2.el7.x86_64.rpm | 289 kB 00:00:00
(11/11): subversion-libs-1.7.14-14.el7.x86_64.rpm | 922 kB 00:00:00
---------------------------------------------------------------------------------------------------------------------------------------------------------------
Total 12 MB/s | 3.6 MB 00:00:00
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Warning: RPMDB altered outside of yum.
Installing : apr-1.4.8-3.el7_4.1.x86_64 1/11
Installing : apr-util-1.5.2-6.el7.x86_64 2/11
Installing : pakchois-0.4-10.el7.x86_64 3/11
Installing : nettle-2.7.1-8.el7.x86_64 4/11
Installing : libmodman-2.0.1-8.el7.x86_64 5/11
Installing : libproxy-0.4.11-11.el7.x86_64 6/11
Installing : trousers-0.3.14-2.el7.x86_64 7/11
Installing : gnutls-3.3.29-9.el7_6.x86_64 8/11
Installing : neon-0.30.0-3.el7.x86_64 9/11
Installing : subversion-libs-1.7.14-14.el7.x86_64 10/11
Installing : subversion-1.7.14-14.el7.x86_64 11/11
Verifying : trousers-0.3.14-2.el7.x86_64 1/11
Verifying : libmodman-2.0.1-8.el7.x86_64 2/11
Verifying : neon-0.30.0-3.el7.x86_64 3/11
Verifying : subversion-1.7.14-14.el7.x86_64 4/11
Verifying : subversion-libs-1.7.14-14.el7.x86_64 5/11
Verifying : apr-util-1.5.2-6.el7.x86_64 6/11
Verifying : nettle-2.7.1-8.el7.x86_64 7/11
Verifying : pakchois-0.4-10.el7.x86_64 8/11
Verifying : gnutls-3.3.29-9.el7_6.x86_64 9/11
Verifying : apr-1.4.8-3.el7_4.1.x86_64 10/11
Verifying : libproxy-0.4.11-11.el7.x86_64 11/11
Installed:
subversion.x86_64 0:1.7.14-14.el7
Dependency Installed:
apr.x86_64 0:1.4.8-3.el7_4.1 apr-util.x86_64 0:1.5.2-6.el7 gnutls.x86_64 0:3.3.29-9.el7_6 libmodman.x86_64 0:2.0.1-8.el7
libproxy.x86_64 0:0.4.11-11.el7 neon.x86_64 0:0.30.0-3.el7 nettle.x86_64 0:2.7.1-8.el7 pakchois.x86_64 0:0.4-10.el7
subversion-libs.x86_64 0:1.7.14-14.el7 trousers.x86_64 0:0.3.14-2.el7
Complete!
碰到一样的问题了，阿里这太苟了
就是得有个取舍了，如果想用阿里提供的镜像源，又想用第三方DNS的话，可以尝试将系统的yum源更换为阿里外网的公共镜像源或其它镜像源