这是一个在 Linode 上运行 Ubuntu 12.04 LTS 的 Drupal 网站。服务器只是一个网站。它不是 DNS 服务器或其他任何服务器。
这是我的问题。看来它们都与 DNS 问题有关。 （我已经用 Linode 解决这个问题几天了，我也在这里获得有关 iptables 的帮助。现在我可以专注于这个问题中的问题了。）
我们的 Mollom 垃圾邮件防护在 Drupal 站点上不起作用，因为服务器无法访问外部服务。 （更多详情见下文）
Drupal 报告：“您的系统或网络配置不允许 Drupal 访问网页，导致功能减少。” （更多详细信息如下 - 我们的 Drupal 配置没有改变）
服务器无法 ping 通互联网
ping google.com ping: unknown host google.com其他网络服务失败。例如：
$ sudo ntpdate ntp.ubuntu.com Exiting, name server cannot be used: Temporary failure in name resolution (-3) 1 Jun 16:42:34 ntpdate[7420]: name server cannot be used: Temporary failure in name resolution (-3) apt-get update Err http://us.archive.ubuntu.com precise Release.gpg Temporary failure resolving 'us.archive.ubuntu.com' Err http://security.ubuntu.com precise-security Release.gpg Temporary failure resolving 'security.ubuntu.com'服务器运行得很差。类似下面的错误是否与无法访问互联网有关？
Out of memory: Kill process 2300 (mysqld) score 129 or sacrifice child Killed process 2300 (mysqld) total-vm:354780kB, anon-rss:53180kB, file-rss:0kB Out of memory: Kill process 5937 (mysqld) score 60 or sacrifice child Killed process 5937 (mysqld) total-vm:344040kB, anon-rss:78988kB, file-rss:0kB
以下是 Drupal 错误的更详细信息。在这些错误发生之前，Drupal 配置没有更改（据我所知）。
HTTP 请求状态失败 您的系统或网络配置不允许 Drupal 访问网页，导致功能减少。这可能是由于您的网络服务器配置或 PHP 设置造成的，应该解决该问题，以便下载有关可用更新的信息、获取聚合器源、通过 OpenID 登录或使用其他依赖于网络的服务。如果您确定 Drupal 可以访问网页，但仍然看到此消息，您可以添加 $conf['drupal_http_request_fails'] = FALSE;到 settings.php 文件的底部。
Mollom API keys Service error The Mollom API keys could not be verified. Please try again later. This issue prevents members from registering for our site or posting comments.
以下是我认为可能相关的信息：
root@example1:/etc# cat /etc/resolv.conf
# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
# DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN
nameserver 789.456.123.6
nameserver 789.456.123.7
root@example1:/etc# cat /etc/hosts
#127.0.0.1 localhost
127.0.1.1 example1.local example1
192.168.150.8 example1 example1
123.456.789.55 example1.example.com example1 www.example.com
root@example1:/etc# cat /etc/nsswitch.conf
# /etc/nsswitch.conf
#
# Example configuration of GNU Name Service Switch functionality.
# If you have the `glibc-doc-reference' and `info' packages installed, try:
# `info libc "Name Service Switch"' for information about this file.
passwd: compat
group: compat
shadow: compat
hosts: files dns
networks: files
protocols: db files
services: db files
ethers: db files
rpc: db files
netgroup: nis
root@example1:/etc# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 123.456.789.1 0.0.0.0 UG 100 0 0 eth0
123.456.789.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
192.168.100.0 0.0.0.0 255.255.128.0 U 0 0 0 eth0
root@example1:/etc# cat /etc/network/interfaces
# The loopback network interface
auto lo
iface lo inet loopback
# This line ensures that the interface will be brought up during boot.
auto eth0 eth0:0
iface eth0 inet static
address 123.456.789.55
netmask 255.255.255.0
gateway 123.456.789.1
dns-nameservers 789.456.123.6 789.456.123.7
# eth0:0 - Private IPs have no gateway (they are not publicly routable) so all you need to specify is the address and netmask.
iface eth0:0 inet static
address 192.168.150.8
netmask 255.255.128.0
root@example1:/etc# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: dummy0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN
link/ether 76:49:bf:95:98:68 brd ff:ff:ff:ff:ff:ff
3: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether xx:xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff
inet 192.168.150.8/17 brd 192.168.255.255 scope global eth0:0
valid_lft forever preferred_lft forever
inet 123.456.789.55/24 brd 123.456.789.255 scope global eth0
valid_lft forever preferred_lft forever
inet6 1000:aaaa::aaaa:aaaa:aaaa:aaa/64 scope global dynamic
valid_lft 2591730sec preferred_lft 604530sec
inet6 fe80::aaaa:aaa:fffff:ffff/64 scope link
valid_lft forever preferred_lft forever
4: teql0: <NOARP> mtu 1500 qdisc noop state DOWN qlen 100
link/void
5: tunl0: <NOARP> mtu 1480 qdisc noop state DOWN
link/ipip 0.0.0.0 brd 0.0.0.0
6: gre0: <NOARP> mtu 1476 qdisc noop state DOWN
link/gre 0.0.0.0 brd 0.0.0.0
7: sit0: <NOARP> mtu 1480 qdisc noop state DOWN
link/sit 0.0.0.0 brd 0.0.0.0
8: ip6tnl0: <NOARP> mtu 1452 qdisc noop state DOWN
link/tunnel6 :: brd ::
9: ip6gre0: <NOARP> mtu 1448 qdisc noop state DOWN
link/[823] 00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00 brd 00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00
root@example1:/etc# ifconfig
eth0 Link encap:Ethernet HWaddr xx:xx:xx:xx:xx:xx
inet addr:123.456.789.55 Bcast:123.456.789.255 Mask:255.255.255.0
inet6 addr: 1000:aaaa::aaaa:aaaa:aaaa:aaa/64 Scope:Global
inet6 addr: fe80::aaaa:aaa:fffff:ffff/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:66713 errors:0 dropped:0 overruns:0 frame:0
TX packets:54198 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:7588512 (7.5 MB) TX bytes:67678447 (67.6 MB)
Interrupt:77
eth0:0 Link encap:Ethernet HWaddr xx:xx:xx:xx:xx:xx
inet addr:192.168.150.8 Bcast:192.168.255.255 Mask:255.255.128.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
Interrupt:77
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:13579 errors:0 dropped:0 overruns:0 frame:0
TX packets:13579 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:852371 (852.3 KB) TX bytes:852371 (852.3 KB)
root@example1:/etc#
以下是更多信息：
# ping -n 789.456.123.7
PING 789.456.123.7 (789.456.123.7) 56(84) bytes of data.
64 bytes from 789.456.123.7: icmp_req=1 ttl=63 time=2.46 ms
64 bytes from 789.456.123.7: icmp_req=2 ttl=63 time=1.80 ms
^C
--- 789.456.123.7 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1001ms
rtt min/avg/max/mdev = 1.802/2.132/2.462/0.330 ms
ping -n 173.194.37.100 (NOTE: this is google.com)
PING 173.194.37.100 (173.194.37.100) 56(84) bytes of data.
64 bytes from 173.194.37.100: icmp_req=1 ttl=55 time=14.2 ms
64 bytes from 173.194.37.100: icmp_req=2 ttl=55 time=14.1 ms
64 bytes from 173.194.37.100: icmp_req=3 ttl=55 time=14.5 ms
^C
--- 173.194.37.100 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2002ms
rtt min/avg/max/mdev = 14.188/14.325/14.513/0.168 ms
以及更多信息：
root@example1:/etc# dig google.com
; <<>> DiG 9.8.1-P1 <<>> google.com
;; global options: +cmd
;; connection timed out; no servers could be reached
root@example1:/etc# dig www.google.com @8.8.8.8
; <<>> DiG 9.8.1-P1 <<>> www.google.com @8.8.8.8
;; global options: +cmd
;; connection timed out; no servers could be reached
root@example1:/etc# ping 8.8.8.8
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
64 bytes from 8.8.8.8: icmp_req=1 ttl=51 time=1.05 ms
64 bytes from 8.8.8.8: icmp_req=2 ttl=51 time=1.08 ms
--- 8.8.8.8 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1001ms
rtt min/avg/max/mdev = 1.058/1.073/1.089/0.036 ms
root@example1:/etc# traceroute google.com
google.com: Temporary failure in name resolution
Cannot handle "host" cmdline arg `google.com' on position 1 (argc 1)
# The following lines are desirable for IPv6 capable hosts
::1 ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
虽然我无法以通常的方式到达 Ubuntu 存储库来安装软件，但我在本地下载了 nmap，然后使用 SCP 将 deb 包复制到服务器。
以下是结果nmap -sS -sU -p 53：
Host is up (0.00085s latency).
PORT STATE SERVICE
53/tcp open domain
53/udp open domain
答案1
关闭防火墙以检测防火墙问题，或添加规则以接受端口 53 上的 UDP。也可以允许端口 53 上的 TCP。尝试控制配置更改并保留所有重要配置文件的备份。