i have raised this with support but though i may use the collective knowledge on here as well.
I have Citect SCADA 2018 system with redundant servers configuration (Primary and Standby) with hard Disk Drive I/O device
Variables.
I have found that these 2 devices do not fully synchronise, the original project when these iO device were added was in 1996 on very early version (V3.21)
Reading the Help directory I now see improved performance and synchronisation is available from V7.2 onwards by using Persisted Memory I/O Device
I will implement this change as soon as I have a down day by the following procedure.
To migrate disk PLC devices to persisted I/O memory mode:
- 1. Perform the procedures listed in Upgrading to Citect SCADA 7.20, as is appropriate. Refer to the v7.20 documentation for more information.
- 2. For disk I/O devices, set the Background Poll property to TRUE and the Persist property to TRUE (the default setting). See Add an I/O Device) for more information.
- 3. Start the I/O server up and wait for a few minutes so that the background poll updates every tag.
- 4. Shutdown the I/O server.
- 5. On the I/O Device dialog, for disk I/O devices set Background Poll back to FALSE, set Memory to TRUE and clear out the Port Name field as it is not necessary for Memory Mode.
- 6. Restart the I/O server to finish the migration to persisted memory I/O mode, with your devices now containing your original values from the disk I/O device.
MY Questions are
Q1 The variables I have in these I/O devices are VERY critical to my process. are these variable Values backed up as part of a Project backup ? if Not is there a way to back up the Values of Disk IO Device Variables
Q2 As I have redundant servers in operation. I would assume I do the above by
- shutting down my Standby server
- do the Above Migration procedure
- restart the Standby server
- shutting down my Primary server
- do the Above Migration procedure
- restart the Primary server
is this correct ? anything else I need to be aware of
Regards
Alan
