我正在运行 Ubuntu 13.04。我安装了 Chrome 和 Firefox，前者无法加载大多数网站。没有代理，我已经禁用了防火墙。我直接通过以太网端口连接到互联网。电脑在办公室，我无法访问任何其他硬件（路由器和类似的东西）。
这是某些网络命令的输出：
root@I39549:~# iptables -t filter --list
Chain INPUT (policy ACCEPT)
target prot opt source destination
ufw-before-logging-input all -- anywhere anywhere
ufw-before-input all -- anywhere anywhere
ufw-after-input all -- anywhere anywhere
ufw-after-logging-input all -- anywhere anywhere
ufw-reject-input all -- anywhere anywhere
ufw-track-input all -- anywhere anywhere
Chain FORWARD (policy ACCEPT)
target prot opt source destination
ufw-before-logging-forward all -- anywhere anywhere
ufw-before-forward all -- anywhere anywhere
ufw-after-forward all -- anywhere anywhere
ufw-after-logging-forward all -- anywhere anywhere
ufw-reject-forward all -- anywhere anywhere
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
ufw-before-logging-output all -- anywhere anywhere
ufw-before-output all -- anywhere anywhere
ufw-after-output all -- anywhere anywhere
ufw-after-logging-output all -- anywhere anywhere
ufw-reject-output all -- anywhere anywhere
ufw-track-output all -- anywhere anywhere
Chain ufw-after-forward (1 references)
target prot opt source destination
Chain ufw-after-input (1 references)
target prot opt source destination
Chain ufw-after-logging-forward (1 references)
target prot opt source destination
Chain ufw-after-logging-input (1 references)
target prot opt source destination
Chain ufw-after-logging-output (1 references)
target prot opt source destination
Chain ufw-after-output (1 references)
target prot opt source destination
Chain ufw-before-forward (1 references)
target prot opt source destination
Chain ufw-before-input (1 references)
target prot opt source destination
Chain ufw-before-logging-forward (1 references)
target prot opt source destination
Chain ufw-before-logging-input (1 references)
target prot opt source destination
Chain ufw-before-logging-output (1 references)
target prot opt source destination
Chain ufw-before-output (1 references)
target prot opt source destination
Chain ufw-reject-forward (1 references)
target prot opt source destination
Chain ufw-reject-input (1 references)
target prot opt source destination
Chain ufw-reject-output (1 references)
target prot opt source destination
Chain ufw-track-input (1 references)
target prot opt source destination
Chain ufw-track-output (1 references)
target prot opt source destination
root@I39549:~# ifconfig
eth0 Link encap:Ethernet HWaddr c8:1f:66:a7:ed:5c
inet addr:10.4.3.174 Bcast:10.4.255.255 Mask:255.255.0.0
inet6 addr: fe80::ca1f:66ff:fea7:ed5c/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:3165125 errors:0 dropped:0 overruns:0 frame:0
TX packets:246303 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:779916007 (779.9 MB) TX bytes:28964602 (28.9 MB)
Interrupt:20 Memory:f7e00000-f7e20000
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:17170 errors:0 dropped:0 overruns:0 frame:0
TX packets:17170 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:1568486 (1.5 MB) TX bytes:1568486 (1.5 MB)
root@I39549:~# cat /etc/hosts
127.0.0.1 localhost
127.0.1.1 I39549
# 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
root@I39549:~# 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 127.0.1.1
search utadeo.edu.co
root@I39549:~# arp -a
ET0021B7F27301.local (169.254.1.2) at 00:21:b7:f2:73:01 [ether] on eth0
portatilrok.utadeo.edu.co (10.4.3.213) at a4:1f:72:8b:47:c4 [ether] on eth0
i37386.local (10.4.1.61) at a8:20:66:06:6d:b1 [ether] on eth0
ET000400C16250.local (10.4.5.88) at 00:04:00:c1:62:50 [ether] on eth0
i58068.utadeo.loc (10.4.1.232) at 00:26:2d:1f:88:9a [ether] on eth0
ET0021B7CC3789.local (169.254.1.10) at 00:21:b7:cc:37:89 [ether] on eth0
? (10.4.0.1) at 00:e0:b1:66:b5:60 [ether] on eth0
i36903.utadeo.loc (10.4.1.7) at d4:9a:20:ec:f2:7e [ether] on eth0
ET000400C1C2B5.local (10.4.5.86) at 00:04:00:c1:c2:b5 [ether] on eth0
i36915.utadeo.loc (10.4.1.190) at a8:20:66:06:6c:d3 [ether] on eth0
root@I39549:~# ping localhost
PING localhost (127.0.0.1) 56(84) bytes of data.
64 bytes from localhost (127.0.0.1): icmp_seq=1 ttl=64 time=0.026 ms
64 bytes from localhost (127.0.0.1): icmp_seq=2 ttl=64 time=0.028 ms
64 bytes from localhost (127.0.0.1): icmp_seq=3 ttl=64 time=0.053 ms
^C
--- localhost ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 1998ms
rtt min/avg/max/mdev = 0.026/0.035/0.053/0.014 ms
root@I39549:~# ping www.google.com
PING www.google.com (74.125.229.211) 56(84) bytes of data.
64 bytes from mia04s05-in-f19.1e100.net (74.125.229.211): icmp_seq=1 ttl=55 time=46.8 ms
64 bytes from mia04s05-in-f19.1e100.net (74.125.229.211): icmp_seq=2 ttl=55 time=46.3 ms
64 bytes from mia04s05-in-f19.1e100.net (74.125.229.211): icmp_seq=3 ttl=55 time=45.9 ms
^C
--- www.google.com ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2002ms
rtt min/avg/max/mdev = 45.958/46.379/46.841/0.438 ms
对于可能存在什么问题，您有什么想法吗？
我已经尝试过这个：
没有任何效果。