问题
在本地网络的Ubuntu 16.04中为kurento-media-server(版本 6.7.0)配置 UFW 时,我有非常奇怪的经历。我的节点应用程序和 KMS 都安装在同一台服务器上,运行在不同的端口上。禁用 UFW 后,该应用程序运行良好,并且节点应用程序与 KMS 一起运行良好。现在,我激活 ufw 并将其配置为
- 允许进出 kurento-media-server 监听端口(8888)
- 允许通过所有UDP端口进出连接,
- 允许通过节点应用程序的监听端口,
- 允许路由,
- 其他常见的 ufw 规则,如 ufw 允许80、443、53等
该应用程序将无法连接到 KMS。似乎 WebSocket 握手卡在某种缓冲区中。
配置完成后,KMS 将不会连接到应用程序。此外,据我所知,ufw 不会干扰本地主机连接。但是与的连接ws://localhost:8888/kurento
只是卡在环回中。
安装源码链接
配置文件 ( /etc/kurento/kurento.conf.json
)
{
"mediaServer" : {
"resources": {
// //Resources usage limit for raising an exception when an
// object creation is attempted
// "exceptionLimit": "0.8",
// // Resources usage limit for restarting the server when no
// objects are alive
// "killLimit": "0.7",
// Garbage collector period in seconds
"garbageCollectorPeriod": 240
},
"net" : {
"websocket": {
"port": 8888,
//"secure": {
// "port": 8433,
// "certificate": "defaultCertificate.pem",
// "password": ""
//},
//"registrar": {
// "address": "ws://localhost:9090",
// "localAddress": "localhost"
//},
"path": "kurento",
"threads": 10
}
}
}
}
UFW 实验:
- 启用ufw后,所有三个,传入,传出,路由都被允许不受任何限制,然后kms也不会连接。
- 为了找出根本原因,我使用Simple WebSocket Client
ws_uri
检查了连接。即使这样也给出了相同的结果;禁用 ufw 时连接成功,启用 ufw 时未连接并在超时后收到警报。undefined
知识管理系统问题
在每次连接失败后,无论是使用 Node App(基本上是节点包kurento-client)还是 Simple WebSocket Client,我都不能简单地禁用 UFW 并完成所有事情。我必须重新启动系统,禁用防火墙(ufw)并启动 kurento-media-server-6.0。甚至sudo service kurento-media-server-6.0 restart
没有帮助。
tcpdump 输出:
tcpdump -vv -i lo port 8888 and '(tcp-syn|tcp-ack)!=0'
成功时
tcpdump: listening on lo, link-type EN10MB (Ethernet), capture size
262144 bytes
13:04:30.904489 IP (tos 0x0, ttl 64, id 51739, offset 0, flags [DF],
proto TCP (6), length 316)
localhost.48866 > localhost.8888: Flags [P.], cksum 0xff30 (incorrect
-> 0xf928), seq 1016466694:1016466958, ack 1363142683, win 3637,
options [nop,nop,TS val 2501898228 ecr 2501846491], length 264
13:04:30.904729 IP (tos 0x0, ttl 64, id 51740, offset 0, flags [DF],
proto TCP (6), length 298)
localhost.48866 > localhost.8888: Flags [P.], cksum 0xff1e (incorrect
-> 0xc0e7), seq 264:510, ack 1, win 3637, options [nop,nop,TS val
2501898228 ecr 2501846491], length 246
13:04:30.906243 IP (tos 0x0, ttl 64, id 43249, offset 0, flags [DF],
proto TCP (6), length 52)
localhost.8888 > localhost.48866: Flags [.], cksum 0xfe28 (incorrect -
> 0x009f), seq 1, ack 510, win 1891, options [nop,nop,TS val
2501898228 ecr 2501898228], length 0
13:04:30.906293 IP (tos 0x0, ttl 64, id 43250, offset 0, flags [DF],
proto TCP (6), length 155)
localhost.8888 > localhost.48866: Flags [P.], cksum 0xfe8f (incorrect
-> 0xd653), seq 1:104, ack 510, win 1891, options [nop,nop,TS val
2501898230 ecr 2501898228], length 103
失败时
tcpdump: listening on lo, link-type EN10MB (Ethernet), capture size
262144 bytes
13:13:14.951036 IP (tos 0x0, ttl 64, id 22976, offset 0, flags [DF],
proto TCP (6), length 60)
localhost.53530 > localhost.8888: Flags [S], cksum 0xfe30 (incorrect -
> 0x270b), seq 3285074519, win 43690, options [mss 65495,sackOK,TS val
2502422275 ecr 0,nop,wscale 7], length 0
13:13:22.531679 IP (tos 0x0, ttl 64, id 28371, offset 0, flags [DF],
proto TCP (6), length 60)
localhost.55238 > localhost.8888: Flags [S], cksum 0xfe30 (incorrect -
> 0x1a57), seq 3772583348, win 43690, options [mss 65495,sackOK,TS val
2502429855 ecr 0,nop,wscale 7], length 0
13:13:23.559036 IP (tos 0x0, ttl 64, id 28372, offset 0, flags [DF],
proto TCP (6), length 60)
localhost.55238 > localhost.8888: Flags [S], cksum 0xfe30 (incorrect -
> 0x1654), seq 3772583348, win 43690, options [mss 65495,sackOK,TS val
2502430882 ecr 0,nop,wscale 7], length 0
13:13:25.575055 IP (tos 0x0, ttl 64, id 28373, offset 0, flags [DF],
proto TCP (6), length 60)
localhost.55238 > localhost.8888: Flags [S], cksum 0xfe30 (incorrect -
> 0x0e74), seq 3772583348, win 43690, options [mss 65495,sackOK,TS val
2502432898 ecr 0,nop,wscale 7], length 0
13:13:29.799248 IP (tos 0x0, ttl 64, id 28374, offset 0, flags [DF],
proto TCP (6), length 60)
localhost.55238 > localhost.8888: Flags [S], cksum 0xfe30 (incorrect -
> 0xfdf2), seq 3772583348, win 43690, options [mss 65495,sackOK,TS val
2502437123 ecr 0,nop,wscale 7], length 0
13:13:37.990986 IP (tos 0x0, ttl 64, id 28375, offset 0, flags [DF],
proto TCP (6), length 60)
localhost.55238 > localhost.8888: Flags [S], cksum 0xfe30 (incorrect -
> 0xddf3), seq 3772583348, win 43690, options [mss 65495,sackOK,TS val
2502445314 ecr 0,nop,wscale 7], length 0