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Looping telnet?

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The Question is:

 
Hi,
 
I am running DIGITAL TCP/IP Services V5.0 on a bunch of Alpha's (and one VAX)
 running VMS V7.2. We have been quite concerned here with the amount of
 network traffic, which we couldn't account for, until recently, when we
 discovered that it seems to be du
e to a faulty telnet server. The following picture is fully reproducible, and
 is the same on both Alpha and VAX:
 
When a user connects via telnet, and he has set his terminal type  to VT100
 prior to issuing the "telnet" command, the activity on the incoming port on
 the server looks typically like this, after about  20 seconds:
 
TCPIP> sho dev/ful bg5255
Device_socket: bg5255      Type: STREAM      LOCAL               REMOTE
                              Port:             23                 5640
                              Host:     vang                130.237.208.43
                              Service:  TELNET
 
                                                           RECEIVE       SEND
                                   Queued I/O                    0
 0       Q0LEN         0             Socket buffer bytes           0
  0       QLEN          0             Socket buffer quota        4380
 4380       QLIMIT
      0             Total buffer alloc            0             0       TIMEO
       0             Total buffer limit        35040         35040       ERROR
        0             Number of XONs                0             0
 OOBMARK       0
     Number of XOFFs               0             0
      I/O completed                17            47
       Bytes transferred            79          1521
  Options:  REUSEADR KEEP
  State:    ISCONNECTED PRIV ASYNC
  RCV Buff: ASYNC
  SND Buff: ASYNC
 
If, however, the user has set his terminal type to  UNKNOWN or "xterm" , the
 corresponding display is:
 
TCPIP> sho dev/ful bg5270
Device_socket: bg5270      Type: STREAM      LOCAL               REMOTE
                              Port:             23                 5642
                              Host:     vang                130.237.208.43
                              Service:  TELNET
 
                                                           RECEIVE       SEND
                                   Queued I/O                    0
 0       Q0LEN         0             Socket buffer bytes           0
  6       QLEN          0             Socket buffer quota        4380
 4380       QLIMIT
      0             Total buffer alloc            0           512       TIMEO
       0             Total buffer limit        35040         35040       ERROR
        0             Number of XONs                0             0
 OOBMARK       0
     Number of XOFFs               0             0
      I/O completed             26162         26187
       Bytes transferred        296312        158300
  Options:  REUSEADR KEEP
  State:    ISCONNECTED PRIV ASYNC
  RCV Buff: ASYNC
  SND Buff: ASYNC
 
Note the horrendous byte counts! In fact the amount of data transferred is only
 limited by the netwrok speed and the CPU power, and is going at this rate
 until the user logs off.
 
The picture is the same regardless of where the user connects from, be it a
 Unix or VMS node.
 
Rlogin does not show the same behaviour.
 
Has anyone seen this before? Is there a patch for it? I haven't been able to
 locate any patch for TCP/IP V5.0.
 
 
          Best regards,
 
                   Torbjorn Moa
                   Univ.  of Stockholm, Sweden
 
 
 
 


The Answer is :

 
  Please move to V5.0A.
 

answer written or last revised on ( 28-MAR-2000 )

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