Issue
Attempting to downgrade the ENC-410 or ENC-520 using the Commissioning Wizard can corrupt the ENC file system making the ENC become unusable.
Environment
I/A Series G3, ENC-410, ENC-520
Cause
Attempting to downgrade the ENC-410 or ENC-520 using the Commissioning Wizard can corrupt the ENC file system making the ENC become unusable.
Resolution
Downgrading from one software release to an earlier release can present compatibility problems. This applies particularly to QNX-based ENCs, as binaries for the (QNX) OS are included in dist files. However, at times it may be necessary to install an older release onto a ENC, or to restore a ENC to a known good state. To downgrade a ENC, or otherwise “wipe it clean to start over,” a clean distribution file must first be installed. The following procedure is also detailed in the Niagara AX Platform Guide included with the G3 software.
Installing a clean dist will wipe the file system and install an appropriate version of Niagara platform daemon, resetting the unit to a “near factory state.” Only the following settings are preserved:
• TCP/IP settings
• license files
• brand.properties
All other data is removed from the file system, including station bog files, Px files, modules, etc. In addition, a clean dist restores the factory-default platform credentials and port (3011). Therefore before installing a clean dist file, make sure to backup station files plus any other modules on the ENC you wish to keep.
Remember, that a “Station Backup” creates a dist file that (when restored) includes the same level of software installed at backup time, so instead of (or in addition to) this type of backup, you may wish to use the Station Copier.
Note that after installing a clean dist, you must recommission the ENC, using the Commissioning Wizard.
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To downgrade a QNX-based ENC from any G3 3.x build to an earlier release:
Step 1: Before installing a clean dist file, make sure you have backed up the station files plus any other data and modules on the ENC you wish to keep.
Step 2: Start G3 3.x Workbench and open a platform connection to the ENC.
Step 3: Open the Distribution File Installer and click Cleaning button for the !/cleanDist directory.
Step 4: Select the appropriate clean dist file for the platform and install. The file system clean will take a few minutes, then the ENC will automatically reboot. Wait for the reboot to complete.
Note: After reboot from a clean dist install, the ENC is using default platform credentials and port (3011).
Step 5: Re-install the software versions to the ENC. Use a version of Workbench that runs the same software versions that you want on the UNC, and use the platform Commissioning Wizard to install the desired software build. For details, refer to the section “About the Commissioning Wizard” in the JACE NiagaraAX Install and Startup Guide.
