Question

Server Sent Event, Text Event Stream getting blocked

Posted July 14, 2020 175 views
Firewall

Hi it seems my droplet is blocking Text Event Stream (Server Sent Event) output outside of host. Seems like a firewall issue but not able to find how to open.

These answers are provided by our Community. If you find them useful, show some love by clicking the heart. If you run into issues leave a comment, or add your own answer to help others.

×
1 answer

Hi there @rakibmail22,

I believe that the Server-sent events are just standard HTTP so you should only need port 80 open.

Can you share the output of the following command here:

  • sudo netstat -plant

Also if you have a firewall enabled, can you share the rules as well?

Regards,
Bobby

  • Below is the output. My application is running on port 30180. Other endpoint of this application works fine. Only the endpoint that produces TEXT EVENT STREAM cannot be accessed from outside host.

    Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name    
    tcp        0      0 0.0.0.0:32000           0.0.0.0:*               LISTEN      18963/kube-proxy    
    tcp        0      0 0.0.0.0:30180           0.0.0.0:*               LISTEN      18963/kube-proxy    
    tcp        0      0 127.0.0.1:10248         0.0.0.0:*               LISTEN      18954/kubelet       
    tcp        0      0 0.0.0.0:25000           0.0.0.0:*               LISTEN      19168/python3       
    tcp        0      0 0.0.0.0:31017           0.0.0.0:*               LISTEN      18963/kube-proxy    
    tcp        0      0 127.0.0.1:10249         0.0.0.0:*               LISTEN      18963/kube-proxy    
    tcp        0      0 127.0.0.1:10251         0.0.0.0:*               LISTEN      18964/kube-schedule 
    tcp        0      0 127.0.0.1:10252         0.0.0.0:*               LISTEN      18951/kube-controll 
    tcp        0      0 127.0.0.1:2380          0.0.0.0:*               LISTEN      18952/etcd          
    tcp        0      0 127.0.0.1:10256         0.0.0.0:*               LISTEN      18963/kube-proxy    
    tcp        0      0 0.0.0.0:31409           0.0.0.0:*               LISTEN      18963/kube-proxy    
    tcp        0      0 127.0.0.1:37393         0.0.0.0:*               LISTEN      18950/containerd    
    tcp        0      0 127.0.0.53:53           0.0.0.0:*               LISTEN      803/systemd-resolve 
    tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      1045/sshd           
    tcp        0      0 127.0.0.1:1338          0.0.0.0:*               LISTEN      18950/containerd    
    tcp        0      0 127.0.0.1:44462         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44392         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44374         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44488         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44370         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44358         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44436         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44400         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 10.1.35.1:54518         10.1.35.19:8024         TIME_WAIT   -                   
    tcp        0      0 127.0.0.1:44398         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44478         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:47790         127.0.0.1:16443         ESTABLISHED 18954/kubelet       
    tcp        0      0 127.0.0.1:44458         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44378         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44454         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44390         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44448         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0   3384 139.59.14.156:22        43.230.120.15:39893     ESTABLISHED 19731/sshd: root@pt 
    tcp        0      0 127.0.0.1:44408         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44440         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:47612         127.0.0.1:16443         ESTABLISHED 18964/kube-schedule 
    tcp        0      0 127.0.0.1:44410         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44354         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44452         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:47714         127.0.0.1:16443         ESTABLISHED 18951/kube-controll 
    tcp        0      0 127.0.0.1:44428         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44414         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44472         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44318         127.0.0.1:12379         ESTABLISHED 18952/etcd          
    tcp        0      0 127.0.0.1:44430         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44470         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44416         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44364         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44362         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44356         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44396         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44486         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44476         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44382         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44484         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44420         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 10.1.35.1:54610         10.1.35.19:8024         TIME_WAIT   -                   
    tcp        0      0 127.0.0.1:44366         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44386         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44434         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44474         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 139.59.14.156:22        218.92.0.200:45762      SYN_RECV    -                   
    tcp        0      0 127.0.0.1:44368         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44450         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44380         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44432         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44348         127.0.0.1:12379         ESTABLISHED 18953/flanneld      
    tcp        0      0 127.0.0.1:44406         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44490         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44466         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44394         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44404         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44460         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:47610         127.0.0.1:16443         ESTABLISHED 18963/kube-proxy    
    tcp        0      0 127.0.0.1:44418         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44442         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44376         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44446         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44360         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44388         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44402         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44468         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44480         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44424         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44482         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44438         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44384         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44412         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44372         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44350         127.0.0.1:12379         ESTABLISHED 18953/flanneld      
    tcp        0      0 127.0.0.1:44456         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 10.1.35.1:54562         10.1.35.19:8024         TIME_WAIT   -                   
    tcp        0      0 127.0.0.1:44422         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44426         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp        0      0 127.0.0.1:44464         127.0.0.1:12379         ESTABLISHED 18943/kube-apiserve 
    tcp6       0      0 :::1024                 :::*                    LISTEN      30033/docker-proxy  
    tcp6       0      0 :::10250                :::*                    LISTEN      18954/kubelet       
    tcp6       0      0 :::10255                :::*                    LISTEN      18954/kubelet       
    tcp6       0      0 :::50000                :::*                    LISTEN      30020/docker-proxy  
    tcp6       0      0 :::10257                :::*                    LISTEN      18951/kube-controll 
    tcp6       0      0 :::10259                :::*                    LISTEN      18964/kube-schedule 
    tcp6       0      0 :::22                   :::*                    LISTEN      1045/sshd           
    tcp6       0      0 :::16443                :::*                    LISTEN      18943/kube-apiserve 
    tcp6       0      0 :::12379                :::*                    LISTEN      18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44440         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44438         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:16443         127.0.0.1:47790         ESTABLISHED 18943/kube-apiserve 
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44380         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44362         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44424         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:16443         127.0.0.1:47612         ESTABLISHED 18943/kube-apiserve 
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44484         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44434         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44450         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44416         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44404         ESTABLISHED 18952/etcd          
    tcp6       0      0 ::1:16443               ::1:53422               ESTABLISHED 18943/kube-apiserve 
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44480         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44378         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44464         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44460         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44360         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44442         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44410         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:16443         127.0.0.1:47714         ESTABLISHED 18943/kube-apiserve 
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44412         ESTABLISHED 18952/etcd          
    tcp6       0      0 139.59.14.156:16443     10.1.35.15:59336        ESTABLISHED 18943/kube-apiserve 
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44458         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44318         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44418         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44482         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44348         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44406         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44400         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44386         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44448         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44462         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:16443         127.0.0.1:47610         ESTABLISHED 18943/kube-apiserve 
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44468         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44396         ESTABLISHED 18952/etcd          
    tcp6       0      0 139.59.14.156:16443     10.1.35.17:50222        ESTABLISHED 18943/kube-apiserve 
    tcp6       0      0 ::1:53422               ::1:16443               ESTABLISHED 18943/kube-apiserve 
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44370         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44430         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44422         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44354         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44364         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44490         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44382         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44426         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44392         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44350         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44478         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44358         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44376         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44414         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44472         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44398         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44420         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44466         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44390         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44368         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44374         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44488         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44372         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44436         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44388         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44428         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44384         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44356         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44366         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44470         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44446         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44452         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44474         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44432         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44402         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44456         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44394         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44454         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44476         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44486         ESTABLISHED 18952/etcd          
    tcp6       0      0 127.0.0.1:12379         127.0.0.1:44408         ESTABLISHED 18952/etcd  
    
Submit an Answer