我一直在致力于一个接近完成的项目：只需按一下按钮就能终止我孩子的互联网连接。我基本上通过调用实现了部分解决方案：
ufw 拒绝 IP
杀死他们的互联网的威胁在一半的情况下有效，而上述的方法在剩下的一半中有效。我遇到问题的地方是 YouTube 长视频。有时继续现有连接很方便，但我还希望有一个按钮可以终止所有进出该 IP 的现有流量。事实证明，这比预期要困难得多。
我尝试过 cutt，它似乎甚至无法在 Ubuntu 14.04 上运行。我试过tcpkill。它似乎在运行，但似乎没有做任何事情（我提供了两个以太网接口）并且似乎想要继续运行。虽然我的 ufw 是持久的，但我宁愿立即无状态地终止并删除所有现有连接。
Conntrack 听起来很有希望（http://conntrack-tools.netfilter.org/manual.html），并且有以下内容：
删除一个条目，如果出现以下情况，这可用于阻止流量：
您有一个有状态的规则集，可以阻止处于无效状态的流量。
您已将 /proc/sys/net/ipv4/netfilter/ip_conntrack_tcp_loose 或 /proc/sys/net/netfilter/nf_conntrack_tcp_loose（具体取决于您的内核版本）设置为零。
命令
conntrack -D -s <IP>
似乎删除并显示了某些内容，但 YouTube 视频一直在嗡嗡作响，当我这样做时，我看到连接正在重组
conntrack -L
我已经搞定了
echo 0 > nf_conntrack_tcp_loose
并对其进行cat'ed以确保它卡住，但它似乎并没有删除连接。
我不是 100% 确定“阻止无效状态流量的有状态规则集”是什么意思，但我确实看到了以下规则
DROP all -- 0.0.0.0/0 0.0.0.0/0 ctstate INVALID
当执行“iptables -L -n”时，如果这就是它引用的内容。
我发现了以下内容：
iptables -A INPUT -s "$BLOCK_THIS_IP" -j DROP
它对我不起作用，但这可能是因为它按照允许内部网络上的所有流量的一般规则进行，并且通过重新排序它可能会起作用。我不想将 iptables 命令与 ufw 命令混合使用。鉴于 UFW 已经设置了 iptables 来拒绝任何新连接，在 iptables 中设置一个 drop 似乎是多余的，如果可以的话，我真的不想将 UFW 与 iptable 命令混合在一起。
谁能告诉我如何使用“conntrack -D”来终止与主机之间的现有连接，或者使用其他方式来实现网络或接口关闭然后再恢复的目的？弄清楚如何做到这一点比想象的更加难以捉摸。
谢谢，
标记
我做了一些更多的测试，我想分享一下。
首先，开始仅使用 ssh 连接来检查终止情况。这实际上相当简单。tcpkill方法和conntrack -D方法都有效。（我还尝试使用 nf_conntrack_tcp_loose=1 （我的系统的默认值）并确认您确实需要将其设置为 0 才能使该conntrack -D 方法正常工作）。
我不知道 YouTube 连接是如何运作的，但它们似乎很难被消灭。如果我只调用conntrack -D IP一次方法，它就不会死。但是如果我设置以下循环
while sleep 1 ; do conntrack -D -s 10.42.43.25 ; done
它最终会死亡。
日志是：
conntrack v1.4.1 (conntrack-tools): 17 flow entries have been deleted.
udp 17 10 src=___.___.43.25 dst=___.___.43.1 sport=57859 dport=53 src=___.___.43.1 dst=___.___.43.25 sport=53 dport=57859 mark=0 use=1
tcp 6 431980 ESTABLISHED src=___.___.43.25 dst=___.___.163.19 sport=59023 dport=80 src=___.___.163.19 dst=___.___.221.222 sport=80 dport=59023 [ASSURED] mark=0 use=1
tcp 6 431980 ESTABLISHED src=___.___.43.25 dst=___.___.218.3 sport=59033 dport=443 src=___.___.218.3 dst=___.___.221.222 sport=443 dport=59033 [ASSURED] mark=0 use=1
tcp 6 102 TIME_WAIT src=___.___.43.25 dst=___.___.242.247 sport=59044 dport=443 src=___.___.242.247 dst=___.___.221.222 sport=443 dport=59044 [ASSURED] mark=0 use=1
tcp 6 431980 ESTABLISHED src=___.___.43.25 dst=___.___.247.248 sport=59024 dport=443 src=___.___.247.248 dst=___.___.221.222 sport=443 dport=59024 [ASSURED] mark=0 use=1
tcp 6 299 ESTABLISHED src=___.___.43.25 dst=sss.sss.sss.177 sport=59042 dport=443 src=sss.sss.sss.177 dst=___.___.221.222 sport=443 dport=59042 [ASSURED] mark=0 use=1
udp 17 0 src=___.___.43.25 dst=___.___.43.1 sport=60775 dport=53 src=___.___.43.1 dst=___.___.43.25 sport=53 dport=60775 mark=0 use=1
tcp 6 431980 ESTABLISHED src=___.___.43.25 dst=sss.sss.sss.78 sport=59035 dport=443 src=sss.sss.sss.78 dst=___.___.221.222 sport=443 dport=59035 [ASSURED] mark=0 use=1
tcp 6 97 TIME_WAIT src=___.___.43.25 dst=___.___.234.25 sport=59039 dport=443 src=___.___.234.25 dst=___.___.221.222 sport=443 dport=59039 [ASSURED] mark=0 use=1
udp 17 11 src=___.___.43.25 dst=___.___.43.1 sport=56527 dport=53 src=___.___.43.1 dst=___.___.43.25 sport=53 dport=56527 mark=0 use=1
tcp 6 431980 ESTABLISHED src=___.___.43.25 dst=___.___.218.110 sport=59020 dport=443 src=___.___.218.110 dst=___.___.221.222 sport=443 dport=59020 [ASSURED] mark=0 use=1
tcp 6 431999 ESTABLISHED src=___.___.43.25 dst=sss.sss.sss.177 sport=59043 dport=443 src=sss.sss.sss.177 dst=___.___.221.222 sport=443 dport=59043 [ASSURED] mark=0 use=1
tcp 6 431948 ESTABLISHED src=___.___.43.25 dst=sss.sss.sss.97 sport=59025 dport=443 src=sss.sss.sss.97 dst=___.___.221.222 sport=443 dport=59025 [ASSURED] mark=0 use=1
udp 17 6 src=___.___.43.25 dst=___.___.43.1 sport=53498 dport=53 src=___.___.43.1 dst=___.___.43.25 sport=53 dport=53498 mark=0 use=1
tcp 6 431988 ESTABLISHED src=___.___.43.25 dst=___.___.10.188 sport=58987 dport=5228 src=___.___.10.188 dst=___.___.221.222 sport=5228 dport=58987 [ASSURED] mark=0 use=1
tcp 6 431999 ESTABLISHED src=___.___.43.25 dst=sss.sss.sss.138 sport=59021 dport=443 src=sss.sss.sss.138 dst=___.___.221.222 sport=443 dport=59021 [ASSURED] mark=0 use=1
tcp 6 431979 ESTABLISHED src=___.___.43.25 dst=___.___.103.74 sport=59038 dport=443 src=___.___.103.74 dst=___.___.221.222 sport=443 dport=59038 [ASSURED] mark=0 use=1
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 2 flow entries have been deleted.
tcp 6 299 ESTABLISHED src=___.___.43.25 dst=sss.sss.sss.177 sport=59049 dport=443 src=sss.sss.sss.177 dst=___.___.221.222 sport=443 dport=59049 [ASSURED] mark=0 use=1
tcp 6 299 ESTABLISHED src=___.___.43.25 dst=sss.sss.sss.177 sport=59050 dport=443 src=sss.sss.sss.177 dst=___.___.221.222 sport=443 dport=59050 [ASSURED] mark=0 use=1
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 1 flow entries have been deleted.
tcp 6 299 ESTABLISHED src=___.___.43.25 dst=sss.sss.sss.177 sport=59052 dport=443 src=sss.sss.sss.177 dst=___.___.221.222 sport=443 dport=59052 [ASSURED] mark=0 use=1
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 1 flow entries have been deleted.
tcp 6 299 ESTABLISHED src=___.___.43.25 dst=sss.sss.sss.177 sport=59053 dport=443 src=sss.sss.sss.177 dst=___.___.221.222 sport=443 dport=59053 [ASSURED] mark=0 use=1
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 1 flow entries have been deleted.
tcp 6 431999 ESTABLISHED src=___.___.43.25 dst=sss.sss.sss.177 sport=59055 dport=443 src=sss.sss.sss.177 dst=___.___.221.222 sport=443 dport=59055 [ASSURED] mark=0 use=1
...
tcp 6 299 ESTABLISHED src=___.___.43.25 dst=sss.sss.sss.177 sport=59089 dport=443 src=sss.sss.sss.177 dst=___.___.221.222 sport=443 dport=59089 [ASSURED] mark=0 use=1
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 1 flow entries have been deleted.
tcp 6 300 ESTABLISHED src=___.___.43.25 dst=sss.sss.sss.177 sport=59090 dport=443 src=sss.sss.sss.177 dst=___.___.221.222 sport=443 dport=59090 [ASSURED] mark=0 use=1
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 1 flow entries have been deleted.
tcp 6 299 ESTABLISHED src=___.___.43.25 dst=sss.sss.sss.177 sport=59092 dport=443 src=sss.sss.sss.177 dst=___.___.221.222 sport=443 dport=59092 [ASSURED] mark=0 use=2
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 1 flow entries have been deleted.
tcp 6 300 ESTABLISHED src=___.___.43.25 dst=sss.sss.sss.138 sport=59094 dport=443 src=sss.sss.sss.138 dst=___.___.221.222 sport=443 dport=59094 [ASSURED] mark=0 use=1
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 1 flow entries have been deleted.
tcp 6 299 ESTABLISHED src=___.___.43.25 dst=sss.sss.sss.177 sport=59095 dport=443 src=sss.sss.sss.177 dst=___.___.221.222 sport=443 dport=59095 [ASSURED] mark=0 use=1
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
conntrack v1.4.1 (conntrack-tools): 0 flow entries have been deleted.
... (finally dead)
所以现在的问题是这里发生了什么？在我最初删除所有流后，如何建立流条目？我缺少什么？有没有什么关于这一切是如何工作的，我不能简单地用一次性命令关闭它？
只是更多信息。我确信本地缓冲不会影响我对正在发生的事情的感知。完成一次删除后，我可以看到缓冲区中的数据量继续增长。另外，我可以拍摄很长的视频，并将 YouTube 帧时间大大拖到未来，远远超出缓冲区水印，并且视频可以在更晚的日期工作。
Chain INPUT (policy DROP)
target prot opt source destination
fail2ban-ssh tcp -- 0.0.0.0/0 0.0.0.0/0 multiport dports 22
ufw-before-logging-input all -- 0.0.0.0/0 0.0.0.0/0
ufw-before-input all -- 0.0.0.0/0 0.0.0.0/0
ufw-after-input all -- 0.0.0.0/0 0.0.0.0/0
ufw-after-logging-input all -- 0.0.0.0/0 0.0.0.0/0
ufw-reject-input all -- 0.0.0.0/0 0.0.0.0/0
ufw-track-input all -- 0.0.0.0/0 0.0.0.0/0
Chain FORWARD (policy ACCEPT)
target prot opt source destination
ufw-before-logging-forward all -- 0.0.0.0/0 0.0.0.0/0
ufw-before-forward all -- 0.0.0.0/0 0.0.0.0/0
ufw-after-forward all -- 0.0.0.0/0 0.0.0.0/0
ufw-after-logging-forward all -- 0.0.0.0/0 0.0.0.0/0
ufw-reject-forward all -- 0.0.0.0/0 0.0.0.0/0
ufw-track-forward all -- 0.0.0.0/0 0.0.0.0/0
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
ufw-before-logging-output all -- 0.0.0.0/0 0.0.0.0/0
ufw-before-output all -- 0.0.0.0/0 0.0.0.0/0
ufw-after-output all -- 0.0.0.0/0 0.0.0.0/0
ufw-after-logging-output all -- 0.0.0.0/0 0.0.0.0/0
ufw-reject-output all -- 0.0.0.0/0 0.0.0.0/0
ufw-track-output all -- 0.0.0.0/0 0.0.0.0/0
Chain fail2ban-ssh (1 references)
target prot opt source destination
REJECT all -- 116.31.116.41 0.0.0.0/0 reject-with icmp-port-unreachable
RETURN all -- 0.0.0.0/0 0.0.0.0/0
Chain ufw-after-forward (1 references)
target prot opt source destination
Chain ufw-after-input (1 references)
target prot opt source destination
ufw-skip-to-policy-input udp -- 0.0.0.0/0 0.0.0.0/0 udp dpt:137
ufw-skip-to-policy-input udp -- 0.0.0.0/0 0.0.0.0/0 udp dpt:138
ufw-skip-to-policy-input tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt:139
ufw-skip-to-policy-input tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt:445
ufw-skip-to-policy-input udp -- 0.0.0.0/0 0.0.0.0/0 udp dpt:67
ufw-skip-to-policy-input udp -- 0.0.0.0/0 0.0.0.0/0 udp dpt:68
ufw-skip-to-policy-input all -- 0.0.0.0/0 0.0.0.0/0 ADDRTYPE match dst-type BROADCAST
Chain ufw-after-logging-forward (1 references)
target prot opt source destination
Chain ufw-after-logging-input (1 references)
target prot opt source destination
LOG all -- 0.0.0.0/0 0.0.0.0/0 limit: avg 3/min burst 10 LOG flags 0 level 4 prefix "[UFW BLOCK] "
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
ACCEPT all -- 0.0.0.0/0 0.0.0.0/0 ctstate RELATED,ESTABLISHED
ACCEPT icmp -- 0.0.0.0/0 0.0.0.0/0 icmptype 3
ACCEPT icmp -- 0.0.0.0/0 0.0.0.0/0 icmptype 4
ACCEPT icmp -- 0.0.0.0/0 0.0.0.0/0 icmptype 11
ACCEPT icmp -- 0.0.0.0/0 0.0.0.0/0 icmptype 12
ACCEPT icmp -- 0.0.0.0/0 0.0.0.0/0 icmptype 8
ufw-user-forward all -- 0.0.0.0/0 0.0.0.0/0
Chain ufw-before-input (1 references)
target prot opt source destination
ACCEPT all -- 0.0.0.0/0 0.0.0.0/0
ACCEPT all -- 0.0.0.0/0 0.0.0.0/0 ctstate RELATED,ESTABLISHED
ufw-logging-deny all -- 0.0.0.0/0 0.0.0.0/0 ctstate INVALID
DROP all -- 0.0.0.0/0 0.0.0.0/0 ctstate INVALID
ACCEPT icmp -- 0.0.0.0/0 0.0.0.0/0 icmptype 3
ACCEPT icmp -- 0.0.0.0/0 0.0.0.0/0 icmptype 4
ACCEPT icmp -- 0.0.0.0/0 0.0.0.0/0 icmptype 11
ACCEPT icmp -- 0.0.0.0/0 0.0.0.0/0 icmptype 12
ACCEPT icmp -- 0.0.0.0/0 0.0.0.0/0 icmptype 8
ACCEPT udp -- 0.0.0.0/0 0.0.0.0/0 udp spt:67 dpt:68
ufw-not-local all -- 0.0.0.0/0 0.0.0.0/0
ACCEPT udp -- 0.0.0.0/0 224.0.0.251 udp dpt:5353
ACCEPT udp -- 0.0.0.0/0 239.255.255.250 udp dpt:1900
ufw-user-input all -- 0.0.0.0/0 0.0.0.0/0
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
ACCEPT all -- 0.0.0.0/0 0.0.0.0/0
ACCEPT all -- 0.0.0.0/0 0.0.0.0/0 ctstate RELATED,ESTABLISHED
ufw-user-output all -- 0.0.0.0/0 0.0.0.0/0
Chain ufw-logging-allow (0 references)
target prot opt source destination
LOG all -- 0.0.0.0/0 0.0.0.0/0 limit: avg 3/min burst 10 LOG flags 0 level 4 prefix "[UFW ALLOW] "
Chain ufw-logging-deny (2 references)
target prot opt source destination
RETURN all -- 0.0.0.0/0 0.0.0.0/0 ctstate INVALID limit: avg 3/min burst 10
LOG all -- 0.0.0.0/0 0.0.0.0/0 limit: avg 3/min burst 10 LOG flags 0 level 4 prefix "[UFW BLOCK] "
Chain ufw-not-local (1 references)
target prot opt source destination
RETURN all -- 0.0.0.0/0 0.0.0.0/0 ADDRTYPE match dst-type LOCAL
RETURN all -- 0.0.0.0/0 0.0.0.0/0 ADDRTYPE match dst-type MULTICAST
RETURN all -- 0.0.0.0/0 0.0.0.0/0 ADDRTYPE match dst-type BROADCAST
ufw-logging-deny all -- 0.0.0.0/0 0.0.0.0/0 limit: avg 3/min burst 10
DROP all -- 0.0.0.0/0 0.0.0.0/0
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-skip-to-policy-forward (0 references)
target prot opt source destination
ACCEPT all -- 0.0.0.0/0 0.0.0.0/0
Chain ufw-skip-to-policy-input (7 references)
target prot opt source destination
DROP all -- 0.0.0.0/0 0.0.0.0/0
Chain ufw-skip-to-policy-output (0 references)
target prot opt source destination
ACCEPT all -- 0.0.0.0/0 0.0.0.0/0
Chain ufw-track-forward (1 references)
target prot opt source destination
ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 ctstate NEW
ACCEPT udp -- 0.0.0.0/0 0.0.0.0/0 ctstate NEW
Chain ufw-track-input (1 references)
target prot opt source destination
Chain ufw-track-output (1 references)
target prot opt source destination
ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 ctstate NEW
ACCEPT udp -- 0.0.0.0/0 0.0.0.0/0 ctstate NEW
Chain ufw-user-forward (1 references)
target prot opt source destination
Chain ufw-user-input (1 references)
target prot opt source destination
ACCEPT all -- 10.42.43.25 0.0.0.0/0
ACCEPT all -- 10.42.43.0/24 0.0.0.0/0
Chain ufw-user-limit (0 references)
target prot opt source destination
LOG all -- 0.0.0.0/0 0.0.0.0/0 limit: avg 3/min burst 5 LOG flags 0 level 4 prefix "[UFW LIMIT BLOCK] "
REJECT all -- 0.0.0.0/0 0.0.0.0/0 reject-with icmp-port-unreachable
Chain ufw-user-limit-accept (0 references)
target prot opt source destination
ACCEPT all -- 0.0.0.0/0 0.0.0.0/0
Chain ufw-user-logging-forward (0 references)
target prot opt source destination
Chain ufw-user-logging-input (0 references)
target prot opt source destination
Chain ufw-user-logging-output (0