you sure the firmware for the DTU's are all the same, I remember having issues like this quite often. I believe we also had issue with the physical DTU's, if there was different versions of DTU's connected to a sunray than we had issues when firmware was upgraded. It's been a while since I have worked with them, At the time it was SunRay1 and SunRay1.1 or something like that. Are all your DTU's the same revision?
I really like Sunrays, but they can be very temperamental sometimes.
BTW: im sure you have this but here are additional error codes for the sunrays
1 Sun Ray unit is starting up and is waiting for ethernet link
2 Sun Ray unit is downloading new firmware
3 Sun Ray unit is storing new firmware in its flash memory
4 Either the download or storage of new firmware has failed
5 There is no session to connect with the Sun Ray
6 The server is denying access to the Sun Ray
7 Local pin entry to the smart card has failed
8 In local smartcard pin entry mode
9 There is an over current condition on the USB bus, i.e., the
total number of devices draws too much current. Consider using powered
hub.
11 Server is authenticated by the Sun Ray and the graphic network
connection is encrypted
12 The Sun Ray cannot authenticate the server but the
graphic/keyboard network connection is still being encrypted
13 Server authenticated to the Sun Ray; network connection between
Sun Ray and server not encrypted
14 Server not authenticated to the Sun Ray; graphic/keyboard
network connection is not encrypted
15 The Sun Ray is refusing to talk to the server due to the
server's refusal or inability to authenticate or encrypt the network
connection
16 The Sun Ray USB bus is temporarily busy servicing a high-speed
device, and the keyboard or mouse may not be responsive to user
input.
21 The Sun Ray unit is booting up and is waiting on DHCP IP
address and parameter assignment.
22 The Sun Ray unit is booting up and is now waiting for the initial
connection to a Sun Ray server.
23 The connection between the Sun Ray and the network is down.
Check the network drop cable and (if the network drop cable is
okay) the network switch.
24 The Sun Ray has disconnected from the previous server.
25 The Sun Ray is being redirected to a new server.
26 The Sun Ray has connected to the server and is waiting for
graphics traffic (this is the GNC state).
27 The Sun Ray is broadcasting to locate a Sun Ray server since
either it was not provided with Sun Ray specific DHCP parameters or all
of the specified servers are not responding.
Icon numbers 31 through 34 are the network status display brought up by
the user pressing all three audio keys.
31 The network link is up and not encrypted.
32 The network link is up and graphics/keyboard are encrypted.
33 The network link is up, the server is authenticated and
graphics/keyboard are encrypted.
34 The network link is up, the server is not authenticated and
graphics/keyboard are not encrypted.
50 The server is refusing to talk to the Sun Ray due to the Sun
Ray's refusal or inability to authenticate or encrypt the network
connection
DCHP State Codes
DCHP State Code State Meaning
A DCHP only provided IP address with no additional parameters
B DCHP provided IP address, subnet mask, and router, but Sun
vendor-specific parameters are missing.
C DHCP provided IP address and Sun Ray vendor-sp parameters, but
subnet mask and router are missing.
D DHCP provided all expected parameters.
Power LED
DTU Hardware State Action to Take
Off Check to see if the appliance is plugged in. Replace the appliance.
Amber Hardware fault. Replace the appliance.
Blinking PROM is corrupted. Check that firmware downloads are properly
configured and enabled. Then power cycle the appliance.
Card reader LED remains on even when smart card is removed
