Maybe you can help me with a question on the subject
why in that in connection with a remote oracle server, the folder "etc" from % SDEHOME% .. file : services.sde
of the service line in 5151 is comment "#" and an installation on the same server if it is enabled ?
esri_sde 5151/tcp #ArcSDE for Oracle (same server oracle 11G+ SDE 10)
# esri_sde 5151/tcp ( server independent) client oracle11G + SDE 10