Thursday, February 19, 2015

Master (MDM or DM) switch (promotion)



In case of any failure on primary master (MDM or DM) TWS has the option to promote a new master in real time.

There are 2 cases that we will go thru:
          1) Temporary switch (the new master will act as a primary master until the FINAL job stream is set to run).
          2) Permanent switch (the new master will act as a primary master until a switchmgr command is performed).

1) Temporary switch
The new promoted master will act as a primary master until the FINAL job stream runs after, it will be reverted back to "old" primary master.
To make the switch / promotion run on the target (the command is instant and you will see in CPU screen at "NODE" column the new "MASTER"):

./<TWS_home>/switchmgr

!!! Applicable to any master or to any FTA which has in it's "TYPE" definition column "FULLSTATUS ON"

2) Permanent switch
The new master will act as a primary master until a switchmgr command should be performed on another master only (Back-up, DR etc). 

a) Cancel the FINAL job stream from the current plan.

./<TWS_home>/bin/conman "cancel @#final;noask"

b) Edit and update the FINAL job stream so it can run on the new primary master.

./<TWS_home>/bin/composer "mo @#final;full"

!!! NOTE change the Job Stream Workstation, Job Workstation and the script path

c) Submit to plan the new "FINAL" job stream

./<TWS_home>/bin/conman "sbs @#final;noask"

!!! NOTE If the "FINAL" job stream update was performed using CLI (as above) MAKE sure you will be deleting the "original" "FINAL" job stream. CLI is not replacing the objects is the workstation is change, instead it creates another item

d) Change in the workstation definition the "TYPE" option of the current master from "MANAGER" to fault-tolerant agent "FTA". 


./<TWS_home>/bin/composer "mo cpu <current master>" 

CPUNAME <current master> 
  DESCRIPTION "MASTER CPU"
  OS UNIX
  NODE master.tws.com TCPADDR 31234
  DOMAIN MASTERDM
  FOR MAESTRO
    TYPE MANAGER #change it to FTA
    AUTOLINK ON
    BEHINDFIREWALL OFF
    FULLSTATUS ON
END
e) Change in the workstation definition the "TYPE" option of the master or the fault-tolerant agent "FTA" which will be promoted to primary master to "MANAGER".

./<TWS_home>/bin/composer "mo cpu <future master>" 

CPUNAME <future master>
  DESCRIPTION "BACK-up MASTER CPU"
  OS UNIX
  NODE back-up-master.tws.com TCPADDR 31234
  DOMAIN MASTERDM
  FOR MAESTRO
    TYPE FTA #change it to MANAGER
    AUTOLINK ON
    BEHINDFIREWALL OFF
    FULLSTATUS ON
END
f) Copy the Security file from the <current master> to the <future master>, by doing this we want to make sure the users will have the same rights.

g) Use "switchmgr" function on 
<future master> to switch the <future master> as the current master.

./<TWS_home>/switchmgr

Optional a) Use "switcheventprocessor" on <future master> to switch the event rules processing server to the <future master> master (only if the event rules are being used and are active on <current master>).

./<TWS_home>/conman switcheventprocessor

Optional b) On the <future master>, edit the "globalopts" file and change the master option to the name of the <future master> workstation (this is used mainly for reports).

vi /<TWA_home>/TWS/mozart/globalopts 

# TWS globalopts file on the TWS Master defines attributes
# of the TWS network.
#
#----------------------------------------------------------------------------
company                     =TWS
master=<current master> # change it to <future master>
start                       =0000

!!! IMPORTANT: The multiple-masters domain (e.g. back-up / DR masters and/or "FULLSTATUS ON" FTA's) global settings and its behavior.

3 comments:

  1. Could you please add steps that needs to be performed for moving DWB from Primary master to Backup Master

    ReplyDelete
  2. Hi Vinay,

    It is there: Optional a)

    ReplyDelete
  3. could you please explain about MDM AND DM and kindly send me on email pintukumarsingh2009@gmail.com

    thanks a lot for your explanation

    ReplyDelete