我在更新 YUM 时遇到了问题，在 CURL 方面也遇到了问题。这让我发现了一些需要解决的问题：
root@server [~]# host google.com
;; connection timed out; trying next origin
;; connection timed out; no servers could be reached
root@server [~]# host google.com
google.com has address 216.58.209.238
;; connection timed out; trying next origin
Host google.com not found: 3(NXDOMAIN)
google.com mail is handled by 20 alt1.aspmx.l.google.com.
google.com mail is handled by 10 aspmx.l.google.com.
google.com mail is handled by 40 alt3.aspmx.l.google.com.
google.com mail is handled by 30 alt2.aspmx.l.google.com.
google.com mail is handled by 50 alt4.aspmx.l.google.com.
root@server [~]# host google.com
;; connection timed out; trying next origin
;; connection timed out; no servers could be reached
root@server [~]# host google.com
;; connection timed out; trying next origin
;; connection timed out; no servers could be reached
root@server [~]# host google.com
google.com has address 216.58.209.238
google.com has IPv6 address 2a00:1450:4007:80f::200e
google.com mail is handled by 50 alt4.aspmx.l.google.com.
google.com mail is handled by 10 aspmx.l.google.com.
google.com mail is handled by 20 alt1.aspmx.l.google.com.
google.com mail is handled by 40 alt3.aspmx.l.google.com.
google.com mail is handled by 30 alt2.aspmx.l.google.com.
root@server [~]# host google.com
;; connection timed out; trying next origin
;; connection timed out; no servers could be reached
root@server [~]# host google.com
;; connection timed out; trying next origin
;; connection timed out; no servers could be reached
root@server [~]# host google.com
;; connection timed out; trying next origin
;; connection timed out; no servers could be reached
root@server [~]# host google.com
google.com has address 216.58.209.238
;; connection timed out; trying next origin
;; connection timed out; no servers could be reached
;; connection timed out; trying next origin
;; connection timed out; no servers could be reached
root@server [~]# host google.com
;; connection timed out; trying next origin
Host google.com not found: 3(NXDOMAIN)
root@server [~]# host google.com
google.com has address 216.58.209.238
;; connection timed out; trying next origin
Host google.com not found: 3(NXDOMAIN)
;; connection timed out; trying next origin
;; connection timed out; no servers could be reached
root@server [~]# host google.com
google.com has address 216.58.209.238
google.com has IPv6 address 2a00:1450:4007:80f::200e
google.com mail is handled by 40 alt3.aspmx.l.google.com.
google.com mail is handled by 20 alt1.aspmx.l.google.com.
google.com mail is handled by 50 alt4.aspmx.l.google.com.
google.com mail is handled by 10 aspmx.l.google.com.
google.com mail is handled by 30 alt2.aspmx.l.google.com.
解析.conf：
root@server [~]# cat /etc/resolv.conf
search ovh.net
nameserver 8.8.8.8
nameserver 8.8.4.4
Yum 错误：
root@server [~]# yum update
Loaded plugins: fastestmirror, rhnplugin
Setting up Update Process
Loading mirror speeds from cached hostfile
* cloudlinux-x86_64-server-6: cl-mirror.ptisp.com
http://download.fedoraproject.org/pub/epel/6/x86_64/repodata/repomd.xml: [Errno 14] PYCURL ERROR 6 - "Couldn't resolve host 'download.fedoraproject.org'"
Trying other mirror.
Error: Cannot retrieve repository metadata (repomd.xml) for repository: epel. Please verify its path and try again
有人能给我指出解决方案的正确方向吗？