some Perl puritians wouldn't even use do

  DB<107> my @cmd; { local $"=','; @cmds = < "{@commands} - {@dbs}" > 
+}
 => (
  "HPRMCLI exch create -s EXCHDAGNODE1 - db1",
  "HPRMCLI exch create -s EXCHDAGNODE1 - db2",
  "HPRMCLI exch mount  -h RMEBackupSvr - db1",
  "HPRMCLI exch mount  -h RMEBackupSvr - db2",
  "HPRMCLI exch validate -level Log - db1",
...
[download]

update

> the use of any special variable should be localized:

not any just the ones potentially creating global damage ... =)