ITEM: U3677L

HOWTO AIX: How to resolve an X.25 "Device Busy" condition (4/95)



SCENARIO:
   We are running the X.25 support provided in the AIX V3 Base Operating
   System (BOS).  We're setting up an X.25 attachment to a PSDN and are
   trying to correct an adapter configuration error.  (We entered the
   wrong number of logical channels.)  When we try to do this in SMIT,
   we're stopped with a "Device is Busy" message.

   What is causing this situation?  The complete message is:
      method error (/etc/methods/chgx25)
      Cannot perform the requested function because the specified device
      is busy.

SOLUTION:
   You cannot change attachment characteristics while a process is using
   X.25.  Technically, a process is holding the X.25 device driver open.
   It sometimes takes a bit of detective work, but you will finally be
   able to change the configuration once you've stopped all processes
   using X.25.

   Typical culprits and the solutions are as follows:
   - Kill any xmonitor, xmanage, or xtalk (look for IBMXTALK) processes
     in the process table.  Use "kill -15" on the process ID. Kill levels
     2 and 3 are okay too.  NEVER use kill -9 to stop xmonitor -- this is
     an error in the AIX V3 X.25 Communications Cookbook (GG24-3692-01)
   - Stop any device driver tracing
   - Detach the TCP/IP interface (execute "ifconfig xt0 detach")
   - Stop SNA (via SMIT or via the "stopsrc -s sna" command)
   - Stop OSI
   - Stop HBX-PAD daemon (do a kill -15 on the rxd process)
   - Stop any user-written applications
   - Stop network management daemons
       1. Stop the NetView end user interface
            Top left corner of the interface, click on file, then exit
       2. Stop NetView
             Smit
               Communication Applications and Services 
                 NetView for AIX
                   Control
                    Stop all running daemons
       3. Stop systems monitor
             Smit
               Communication Applications and Services
                 Systems Monitor for AIX
                   Local options 
                     Control SIA    (F4 to list)
                       Stop sysinfod
                     Control MLM    (F4 to list)
                       Stop midmand
   If you have tried all of these things and the device busy message
   persists, skip to the "If all else fails" section at the end of this
   document.

NOTES FOR SYSTEMS RUNNING AIX X.25 LPPS:
   This situation also occurs on AIX systems running one of the new X.25
   LPPs when the following message is posted:
               
      method error (/etc/methods/chgx25)
      0514-029  Cannot perform the requested function because a child
                device of the specified device is not in a correct state.
       
   On these systems, look for things similar to those listed for AIX V3
   BOS.  In addition, the following things are unique to the new LPPs:
   - Stop the IBM Triple-X PAD daemon (x29d)
   - Stop the SNMP daemon (x25smuxd)
   - Stop anything running on COMIO, then remove COMIO Emulation from a
     port to free it.  COMIO emulates the AIX V3 BOS X.25 device driver
     (/dev/x25s0) and allows pre-LPP applications to run unchanged. Thus,
     check for all applications as described in the previous section.
   - Stop any user-written NPI or DLPI applications
   - Bring the TCP/IP xs interface down (it is not necessary to detach)
   - Stop any device driver tracing

IF ALL ELSE FAILS:
   If all else fails and you cannot identify the culprit, the following
   workaround can be used on systems running AIX V3 BOS X.25 support.
   Although this is a way around the situation, it is not an ideal
   solution to the problem because the system must be rebooted.
         The same, general workaround can be used by systems running the X.25
   LPPs -- notes on the differences follow these steps.
   
   1. Rename the /etc/microcode/icaaim.com file so that X.25 will not be
      able to start up at reboot.  Any unique name will do, for example:
         mv icaaim.com Icaaim.com
   2. Shutdown and reboot the system via: 
         shutdown -Fr  
   3. When the system comes back up, make the desired changes in SMIT.
      At this point, the "lsdev -C | grep X.25" command should show that
      ampx0 is Available, but x25s0 is Defined.
   4. Change the icaaim.com file back to the correct name:
         mv Icaaim.com icaaim.com
   5. Either reboot or use the following SMIT progression to reactivate
      the X.25 device driver.
         Smit
           Devices
             Communications
               X.25 CoProcessor/2 or Multiport
                 Adapter
                   Manage an X.25 CoProcessor/2 Device Driver
                     Configure a Defined Device Driver
      The microcode copyright information will be posted.  After process-
      ing has completed, the "lsdev -C | grep X.25" command should show
      that ampx0 and x25s0 are Available.
   6. Restart any applications that were stopped in the previous steps.
   
   AIX X.25 LPP users can follow the same general steps, but there are
   a few modifications.
      
   The adapter microcode, shipped with the LPP software, is found in the
   /usr/lib/asw directory.  The Portmaster/A adapters use the sx25pma.cod
   file while the X.25 Co-Processor adapters (both microchannel and ISA
   bus) use sx25cyc.cod file.  Substitute these names in steps 1 and 4.
      
   In step 3, the adapter (apm0 or ampx0) should be Available, but the
   port (named xs25a\#) should be Defined.  A user can modify a port's
   characteristics as long as that port is in a Defined state -- it isn't
   necessary to disable all of the ports on a single adapter or in a
   system.  When using this workaround, however, all ports of this type
   will become Defined.
   
   In step 5, reactivate by selecting "Configure a Defined Port" in the
   "Manage X.25 Ports" menu, accessed via fastpath "smit x25str_mp" on
   Portmaster and "smit cx25str_mp" on the X.25 Co-Processor systems.
   Users may either bring up the ports/interfaces one-at-a-time with this
   menu or reboot the system to bring them all up together.
   
(April, 1995)



Support Line: HOWTO AIX: How to resolve an X.25 "Device Busy" condition (4/95) ITEM: U3677L
Dated: May 1995 Category: N/A
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