Job causes U00003422 WARNING for server routine UCDVAR_R generating WP Traces

Products

• CA Automic One Automation

Issue/Introduction

Some particular Jobs launched on an Unix Agent can cause a system freeze of the WP process because WP  processes generate forced memory dump traces due to the following error:

 'U00003422 WARNING: Cannot load conversation memory 'XXX' for server routine 'UCDVAR_R'

Example of the traces in WP logs:

20200821/125818.129 - U00003422 WARNING: Cannot load conversation memory '00667e2b' for server routine 'UCDVAR_R'.
20200821/125818.129 - U00009907 Memory dump 'Input memory' (Address='0x7fa6f2054010', Length='304')
20200821/125818.129 - 00000000 51554954 54202020 30310500 0C831100 >QUITT 01...<83>..<
20200821/125818.129 - 00000010 4E4B2020 45585245 51434D44 00000000 >NK EXREQCMD....<
20200821/125818.129 - 00000020 00000000 33851E00 35323731 33383028 >....3<85>..5271380(<
20200821/125818.129 - 00000030 70696420 36393639 297C4E6F 20737563 >pid 6969)|No suc<
20200821/125818.129 - 00000040 68207072 6F636573 737C6C73 202D6C20 >h process|ls -l <
20200821/125818.129 - 00000050 2F6D6C6F 67732F62 7074666F 742F6461 >/mlogs/bptfot/da<
20200821/125818.129 - 00000060 74616669 6C65732F 6F757462 6F756E64 >tafiles/outbound<
20200821/125818.129 - 00000070 2F42495F 4672616D 65776F72 6B2F5343 >/BI_Framework/SC<
20200821/125818.129 - 00000080 4D2F4652 5F494E54 5F2A2032 3E2F6465 >M/FR_INT_* 2>/de<
20200821/125818.129 - 00000090 762F6E75 6C6C7C77 63202D6C 00202020 >v/null|wc -l. <
20200821/125818.129 - 000000A0= 20202020 20202020 20202020 20202020 > <
20200821/125818.129 - 00000120 20202020 20202020 00000000 00000000 > ........<
20200821/125818.131 - U00011801 Error in Server routine 'UCDVAR_R', Server: 'UC4_60#WP005' AE system: 'UC4_60'.
20200821/125818.132 - U00003422 WARNING: Cannot load conversation memory '00667e2b' for server routine 'UCDVAR_R'.
20200821/125818.261 - U00015006 System forced memory trace dump.
20200821/125818.262 - U00015006 System forced memory trace dump.

Environment

Release : 12.1, 12.2 and 12.3

Component : AUTOMATION ENGINE

Issue not present in Automation Engine 12.0.x

Cause

Bug in the Automation Engine and Agent Unix:

if a file-event message is sent to the agent and the agent loses the connection (network issue) the agent must not send this NK message as the Automation Engine core will make automatically a NK for the FH message and once the agent sends it, the entry in the DB can't be found anymore as the WP's already had reset the record which causes the force traces.

Resolution

Workaround: 

Ignore the WP force traces

Solution:

Update to a fix version listed below or a newer version if available.

Fix version:
Component(s): Automation Engine  and Agent Unix

Automation.Engine 12.2.10 - Available
Automation.Engine 12.3.7 - Available
Automation.Engine 21.0.0 - Available