# Designer Launcher Network Name Resolution Issue **URL:** \ **Category:** Ignition\ **Tags:** ignition80\ **Created:** [October 22, 2019, 2:19pm UTC](https://forum.inductiveautomation.com/t/designer-launcher-network-name-resolution-issue/29280 "2019-10-22T14:19:27Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![tim.schultz](https://avatars.discourse-cdn.com/v4/letter/t/71e660/32.png) [@tim.schultz](https://forum.inductiveautomation.com/u/tim.schultz)\ **Post date:** [October 22, 2019, 2:19pm UTC](https://forum.inductiveautomation.com/t/designer-launcher-network-name-resolution-issue/29280/1 "2019-10-22T14:19:27Z")
I have several servers set up in a development pipeline, and have accordingly had our network team give them DNS names. So each gateway has a server name with the pattern \<3 char site code\>V\<4 digit sequence\>, and then a DNS record with the pattern IGN\_\<3 char site code\>\_. As an example: My dev server at site WHQ could be WHQV1234 with DNS name IGN\_WHQ\_DEV. The DesignerLauncher successfully recognizes http://IGN\_WHQ\_DEV:8088 as a valid gateway and lets me add it; however, when I try to launch the Designer, it does not work (I get an error saying “Error launching application: UnknownHostException: null”). If I use the server name (so [http://WHQV1234:8088](http://WHQV1234:8088)) the Designer will successfully launch. Note that I can ping both server and DNS name, I can access Perspective sessions using both server and DNS name… it seems to be just the DesignerLauncher thus far that has issues. Any ideas on why this is failing? ---
**Author:** ![dan123](https://avatars.discourse-cdn.com/v4/letter/d/cc9497/32.png) [@dan123](https://forum.inductiveautomation.com/u/dan123)\ **Post date:** [February 6, 2020, 2:08pm UTC](https://forum.inductiveautomation.com/t/designer-launcher-network-name-resolution-issue/29280/2 "2020-02-06T14:08:30Z")
I’m getting a related issue, so I figured I’d add it here (and to bump this topic since it’s unanswered) – I have Ignition running on a local VM, and I can connect to the web gateway using the server name, and it lets me add the application to the designer using the server name, but I get the same error when trying to launch the Designer (UnknownHostException: null). The only way I can launch the Designer is by using the IP address. ---
**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\ **Post date:** [February 6, 2020, 2:22pm UTC](https://forum.inductiveautomation.com/t/designer-launcher-network-name-resolution-issue/29280/3 "2020-02-06T14:22:15Z")
You happen to have an underscore in your server name as well? ---
**Author:** ![dan123](https://avatars.discourse-cdn.com/v4/letter/d/cc9497/32.png) [@dan123](https://forum.inductiveautomation.com/u/dan123)\ **Post date:** [February 6, 2020, 2:56pm UTC](https://forum.inductiveautomation.com/t/designer-launcher-network-name-resolution-issue/29280/4 "2020-02-06T14:56:00Z")
Ah that’s it! Shoulda figured, ran into that same issue with iFix awhile ago – changing the underscores to dashes fixed it, thanks! ---
**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\ **Post date:** [February 6, 2020, 3:27pm UTC](https://forum.inductiveautomation.com/t/designer-launcher-network-name-resolution-issue/29280/5 "2020-02-06T15:27:20Z")
I think both of you are running into the same issue, which is that ultimately an underscore is not a legal character to appear in the hostname component of a URI/URL. My guess is that when adding a gateway there must be a regex or some other superficial API that doesn’t do validation, but when it comes time to actually connect the validation occurs. Java is pretty strict about URI/URL following the spec. To avoid heartache don’t assign hostnames with underscores if they’re ever going to appear in a URL.