Introduction

If you require to secure your Samba installation with a firewall, you would need information, what ports and protocols are used. This page will give you an overview.

Identify on which ports and interfaces Samba is listening

You can use “netstat” to identify which ports Samba and related daemons are listening on and on which IPs:

 # netstat -tulpn | egrep "samba|smbd|nmbd|winbind"

The following is a snippet of an example output:

 tcp        0      0 127.0.0.1:139               0.0.0.0:*                   LISTEN      43270/smbd          
 tcp        0      0 10.0.0.1:139                0.0.0.0:*                   LISTEN      43270/smbd          
 tcp        0      0 10.0.0.1:88                 0.0.0.0:*                   LISTEN      43273/samba         
 tcp        0      0 127.0.0.1:88                0.0.0.0:*                   LISTEN      43273/samba         
 tcp        0      0 127.0.0.1:445               0.0.0.0:*                   LISTEN      43270/smbd          
 tcp        0      0 10.12.112.84:445            0.0.0.0:*                   LISTEN      43270/smbd          
.....

The above example shows, that the services are listening on localhost (127.0.0.1) and the interface with IP 10.12.112.84 - each on the listed ports (139, 88, 445,…).

Port usage when Samba runs as DC

* Samba, like Windows, supports dynamic RPC services. The range starts at 1024. If something occupies this port for some reason, it will be a different port (literally walked up from 1024).