Have a windows 2008 R2 client with SDE client installed. The sde database is on a linux machine running oracle 11g. Followed all the instructions from this article:
There is nothing that should have prevented your earlier service from starting if the correct entries existed within both the '%SDEHOME/etc/service.sde' and '%WINDIR%\system32\drivers\etc\services'
This is similar to the process necessary to create an ArcSDE service on Linux or Unix:
If any clients will be connecting to the geodatabase using an ArcSDE service, you must alter the operating system services file and the ArcSDE services.sde file. The services.sde file can be found in the $SDEHOME/etc directory.
It appears as though you already had the "esri_sde" service assigned in both these files which is why you did not see the error using that service name. The documentation team has been contacted to include reference to this within the online installation guides as well.
Please note that you can always submit online web-help feedback to our documentation team by clicking on the "Feedback" button in the upper right-hand corner of any page [ATTACH=CONFIG]12398[/ATTACH]