Technical Tip: Cannot change interface IP address and 'Error: IP address x.x.x.x is configured as source-ip for syslog or other servers' is seen

[mpeddalla]

Description	This article describes why it is not possible to change the interface IP address when 'Error: IP address x.x.x.x is configured as source-ip for syslog or other servers' is seen.
Scope	FortiGate.
Solution	As seen in the below image, on the interface it is not possible to change the IP address even though there are no references. The error message refers to the syslogd settings where the interface IP address is being used. It is possible to check where that IP is being used by running the following command (where x.x.x.x is the current IP): show | grep -f x.x.x.x In the below screenshot, the IP address of the interface is referenced in the syslogd server configuration It is possible to make note of changes or take backup configuration files before changes and add them back once if needed accordingly. After confirming all references are gone, it is possible to change the interface IP address to the 0.0.0.0/0.0.0.0 default address (or any other IP).   Once the address is changed, it is possible to use the same address on a different interface and update all existing firewall policies, static routes, etc. If there is a FortiManager, it will be possible to push all changes from FortiManager once the interface address is updated on FortiManager. If there is no FortiManager, it will be necessary to manually change everything.