I am not sure of the command in the server console to check STEAMID’s or if there actually is one.
When typing serverinfo it doesn’t show anything about a clients STEAMID.
example:
client 0: z, ping = 48, rate = 16000
But, if you look in your logs folder in your dedicated server, there is a connection_log<Port#>txt file.
Here is an entry from mine:
[2011-05-17 13:32:18][0,0] : Log session started
[2011-05-17 13:32:18][0,0] : SetSteamID( [A:1:0:0] )
[2011-05-17 13:32:18][1,2] : Connect() starting connection (eNetQOSLevelLow, 81.171.115.5:27017, UDP)
[2011-05-17 13:32:18][1,2] : ConnectionCompleted() (72.165.61.174:27017, UDP)
[2011-05-17 13:32:19][1,2] : RecvMsgClientLogOnResponse() : [A:1:3346977809:2637] 'OK'
[2011-05-17 13:47:06][3,2] : LogOff()
[2011-05-17 13:47:06][2,2] : AsyncDisconnect()
[2011-05-17 13:47:06][2,0] : Log session ended
[2011-05-17 13:47:07][0,0] : Log session started
[2011-05-17 13:47:07][0,0] : SetSteamID( [A:1:0:0] )
[2011-05-17 13:47:07][1,2] : Connect() starting connection (eNetQOSLevelLow, 72.165.61.188:27017, UDP)
[2011-05-17 13:47:08][1,2] : ConnectionCompleted() (68.142.83.181:27017, UDP)
[2011-05-17 13:47:08][1,2] : RecvMsgClientLogOnResponse() : [A:1:3501988883:2637] 'OK'
[2011-05-17 14:09:43][3,2] : LogOff()
[2011-05-17 14:09:43][2,2] : AsyncDisconnect()
[2011-05-17 14:09:43][2,0] : Log session ended
[2011-05-17 14:09:44][0,0] : Log session started
[2011-05-17 14:09:44][0,0] : SetSteamID( [A:1:0:0] )
[2011-05-17 14:09:44][1,2] : Connect() starting connection (eNetQOSLevelLow, 81.171.115.7:27017, UDP)
[2011-05-17 14:09:45][1,2] : ConnectionCompleted() (208.111.133.84:27017, UDP)
[2011-05-17 14:09:45][1,2] : RecvMsgClientLogOnResponse() : [A:1:3504196627:2637] 'OK'
[2011-05-17 15:01:08][3,2] : LogOff()
[2011-05-17 15:01:08][2,2] : AsyncDisconnect()
[2011-05-17 15:01:08][2,0] : Log session ended
As you can see the game sets :SetSteamID( [A:1:0:0] ) to every client that connects.
This is where it gets a little tricky. So I did some poking around. The STEAMID entry is on the last line.
[2011-05-17 14:09:45][1,2] : RecvMsgClientLogOnResponse() : [A:1:3504196627:2637] ‘OK’
The BOLD numbers are PART of the STEAMID. STEAMID’s are parsed like this:
STEAM_0:1:xxxxxxxx
So, with the SteamID Converter
The last entry [2011-05-17 14:09:45][1,2] : RecvMsgClientLogOnResponse() : [A:1:3504196627:2637] ‘OK’
I parsed the Bold id Steam_0:1:3504196622 and found this:
User Profile
SteamID Converter tool snippet originally created BY Voogru of Alliedmodders
I will create a post/request over there to see if any of the programmers will consider making a tool for Brink.
As far as I know, they mostly stick to Source based games.
So, SteamID’s are being checked, we just need someone to make an admin mod/tool.
I hope this clarifies your question. 