pfSense

The VLAN interface page breaks after restoring a backup from devices using emX interfaces to devices using igbX interfaces.
This is rather problemmatic as after the page is broken the only way to fix is to re-image.
The work around is to remove all VLAN interfaces from the configuration before backing up and restoring.

When the page breaks this is the error received:
Fatal error: Cannot redeclare vlan_inuse() (previously declared in /usr/local/www/interfaces_vlan.php:42) in /etc/inc/interfaces.inc on line 272 Call Stack: 0.0026 231112 1. {main}() /usr/local/www/interfaces_vlan.php:0 0.0027 231616 2. require_once('/usr/local/www/guiconfig.inc') /usr/local/www/interfaces_vlan.php:33 0.0029 254168 3. require_once('/etc/inc/authgui.inc') /usr/local/www/guiconfig.inc:51 0.0029 254800 4. include_once('/etc/inc/auth.inc') /etc/inc/authgui.inc:25 0.0029 255232 5. require_once('/etc/inc/config.gui.inc') /etc/inc/auth.inc:31 0.0061 279224 6. require_once('/etc/inc/notices.inc') /etc/inc/config.gui.inc:37 0.0061 279600 7. require_once('/etc/inc/functions.inc') /etc/inc/notices.inc:24 PHP ERROR: Type: 1, File: /etc/inc/interfaces.inc, Line: 272, Message: Cannot redeclare vlan_inuse() (previously declared in /usr/local/www/interfaces_vl an.php:42)

You can reproduce by:

add vlan to 8860 interface
backup config
restore config to vmware device
reassign interfaces as normal.
backup config
restore to 8860
then try and reassign interfaces,
get errors about non existing vlans
attempt to resolve vlan issue on vlan interfaces page.