FME Flow Cannot Run Jobs - Underscore in Host Name

Liz Sanderson
Liz Sanderson
  • Updated

Symptom

After installing FME Flow (formerly FME Server) using a host name which includes underscores (_) you can start FME Flow but when you submit a job, an error is produced. The error may look like :
 Unknown Result No Log file generated.

You may also see a 500 error within the Tomcat logs here: <Install Dir>fmeserver\utilities\tomcat\logs


Cause

Underscores (_) in host names are not supported in FME Flow. Besides not being permissible according to Internet standards (see the article http://en.wikipedia.org/wiki/Hostname and also RFC 952 or RFC 2181) this is also not possible using Apache Tomcat which is the default application server used by FME Flow.


Resolution

A few solutions are possible, but all involve installing FME Flow using a host name which does not contain an underscore:

  • Change the URL of services under System Configuration > Network & Email
  • Change the machine name to one that does not include an underscore
  • Assign a domain name to your host which does not include an underscore and install FME Flow using that domain name
  • If the IP address of the machine is static use this as the host name
  • If FME Flow will only be accessed from the machine it is running on, install FME Flow using localhost as the host name
  • Again if FME Flow will only be accessed from the machine it is running on edit your hosts file (C:\Windows\System32\drivers\etc\hosts) and make an entry which includes a name without underscores and maps this to the local host IP like this: 127.0.0.1 hostname

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