lxc 容器可以 ping 主機並且可以解析 dns 網際網路地址但無法訪問網際網路

Debian Buster amd64

兩個容器 192.168.122.2,3 都可以解析但不能上網

兩個容器都可以 ping / 與主機伺服器互動。

這是我在 iptables 中的內容。

# Generated by xtables-save v1.8.2 on Sat Mar  6 17:16:16 2021  
*filter  
 
:INPUT ACCEPT [47377:13690982]  

:FORWARD ACCEPT [419:628058]  

:OUTPUT ACCEPT [24929:4008372]  

:POSTROUTING - [0:0]  
-A INPUT -p tcp -m tcp --dport 80 -j ACCEPT  
-A INPUT -p tcp -m tcp --dport 443 -j ACCEPT  

-A INPUT -p tcp -m tcp --dport 8080 -j ACCEPT  
-A INPUT -p tcp -m tcp --dport 4430 -j ACCEPT  
-A INPUT -i virbr0 -p udp -m udp --dport 53 -j ACCEPT  
-A INPUT -i virbr0 -p tcp -m tcp --dport 53 -j ACCEPT  
-A INPUT -i virbr0 -p udp -m udp --dport 67 -j ACCEPT  
-A INPUT -i virbr0 -p tcp -m tcp --dport 67 -j ACCEPT  
-A FORWARD -d 192.168.122.2/32 -p tcp -m tcp --dport 80 -j ACCEPT  
-A FORWARD -d 192.168.122.2/32 -p tcp -m tcp --dport 443 -j ACCEPT  
-A FORWARD -d 192.168.122.3/32 -p tcp -m tcp --dport 8080 -j ACCEPT  
-A FORWARD -d 192.168.122.3/32 -p tcp -m tcp --dport 4430 -j ACCEPT  
-A FORWARD -d 192.168.122.0/24 -o virbr0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT  
-A FORWARD -s 192.168.122.0/24 -i enxd03745c9b08e -j ACCEPT  
COMMIT  
# Completed on Sat Mar  6 17:16:16 2021  
# Generated by xtables-save v1.8.2 on Sat Mar  6 17:16:16 2021  
*nat  
:PREROUTING ACCEPT [2101:142603]  
:INPUT ACCEPT [1480:106813]  
:POSTROUTING ACCEPT [430:29500]  
:OUTPUT ACCEPT [329:23520]  
-A PREROUTING -i enxd03745c9b08e -p tcp -m tcp --dport 80 -j DNAT --to-destination  192.168.122.2:80  
-A PREROUTING -i enxd03745c9b08e -p tcp -m tcp --dport 80 -j DNAT --to-destination 192.168.122.2:80  
-A PREROUTING -i enxd03745c9b08e -p tcp -m tcp --dport 443 -j DNAT --to-destination  192.168.122.2:443  
-A PREROUTING -i enxd03745c9b08e -p tcp -m tcp --dport 8080 -j DNAT --to-destination 192.168.122.3:8080  
-A PREROUTING -i enxd03745c9b08e -p tcp -m tcp --dport 4430 -j DNAT --to-destination 192.168.122.3:4430  
COMMIT  
# Completed on Sat Mar  6 17:16:16 2021  
# Generated by xtables-save v1.8.2 on Sat Mar  6 17:16:16 2021  
*mangle  
:PREROUTING ACCEPT [49751:14725298]  
:INPUT ACCEPT [47442:13695764]  
:FORWARD ACCEPT [1555:987308]  
:OUTPUT ACCEPT [24929:4008372]  
:POSTROUTING ACCEPT [26484:4995680]  
COMMIT  
# Completed on Sat Mar  6 17:16:16 2021  

我找到了解決方法。 https://discuss.linuxcontainers.org/t/internet-access-issue-inside-container/5258

我不得不使用 iptables-legacy 並執行以下操作：

/sbin/iptables-legacy -t nat -A POSTROUTING -s 192.168.122.0/24 ! -d 192.168.122.0/24 -p tcp -j MASQUERADE --to-ports 1024-65535  
/sbin/iptables-legacy -t nat -A POSTROUTING -s 192.168.122.0/24 ! -d 192.168.122.0/24 -p udp -j MASQUERADE --to-ports 1024-65535  
/sbin/iptables-legacy -t nat -A POSTROUTING -s 192.168.122.0/24 ! -d 192.168.122.0/24 -j MASQUERADE  

引用自：https://unix.stackexchange.com/questions/637941