I get a failure in name resolution when running annex testremote:

mvanhult@detekti:~/temp/my_repo$ git annex testremote bbborig | head
testremote bbborig (generating test keys...) Remote Tests
  unavailable remote
ssh: Could not resolve hostname !dne!: non-recoverable failure in name resolution
    removeKey:                                       OK (0.01s)
ssh: Could not resolve hostname !dne!: non-recoverable failure in name resolution
    storeKey:                                        OK
ssh: Could not resolve hostname !dne!: non-recoverable failure in name resolution
    checkPresent:                                    OK
ssh: Could not resolve hostname !dne!: non-recoverable failure in name resolution
    retrieveKeyFile:                                 OK
    retrieveKeyFileCheap:                            OK
  key size Just 1048576; remote chunksize=0 encryption=none
The following modules were not unloaded:
  (Use "module --force purge" to unload all):

  1) Stages/2024
    removeKey when not present:                      FAIL
      Exception: removing content from remote failed
mvanhult@detekti:~/temp/my_repo$ git remote -v
bbborig juwels:/p/home/jusers/vanhulten1/juwels/temp/my_repo (fetch)
bbborig juwels:/p/home/jusers/vanhulten1/juwels/temp/my_repo (push)

Where does this !dne! come from? The relevant host of the remote is juwels and not !dne!. I have never before this post entered the string !dne!. Is dne an abbreviation?