Ah, yes, you're right. The problem now is that the machine name is "abcd-efg-hijk", but you need it to be "abcd-efg-hijk.local". Since they don't match exactly, you may run into some problems, but here are a couple of next steps:
1) Generate a new certificate, issued to abcd-efg-hijk.local
2) Set the new certificate as the certificate for 7443.
Now, you won't run into certificate mismatch problems, but the machine name you'd use to reach the Portal doesn't match the machine name the Portal knows itself as. I would try to register the WA using "abcd-efg-hijk.local" and then see if things work out, (federation, etc). If not, then go through the following:
1) In the C:\Windows\System32\drivers\etc\hosts file, add an entry to associate the IP address of the machine with the hostname you want to use:
Ex.
10.0.0.1 abcd-efg-hijk.local
2) Uninstall and reinstall all components. Now each machine will know itself as abcd-efg-hijk.local.
3) Set up the ArcGIS Enterprise.
The ArcGIS Enterprise Builder will honor whatever entry is in the \etc\hosts file so you can use the AEB to set everything up.