Resuming an ArcSDE service using sdemon
Use the sdemon command with the resume operation to restart a remote ArcSDE service from a UNIX, Linux, or Windows server or a local ArcSDE service on UNIX or Linux.
When the service is paused, neither ArcSDE service nor direct connections can be made to the geodatabase until the service is resumed.
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Windows users must have power user or administrator group permissions to pause, resume, or shut down a local or remote ArcSDE service.
Steps:
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At an MS-DOS command prompt (Windows) or shell prompt (UNIX or Linux), type the sdemon command with the resume operation.
sdemon –o resume –p nevermind –s squirrel –i 6543 ArcSDE I/O Manager is Resuming, new connections will now be allowed
8/19/2013