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This directive can be used only with network licenses; accordingly, the the COUNT directive must be set if GRACE is set.
Usage and recommendations
Grace licenses allow users to continue working with an application when the license server goes down. In emergency situations, when no one is available to restart the license server, a time-limited grace license lets the user continue to run the feature. Note that the grace license is available only for the currently logged-in user of the client machine.
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If the server becomes unavailable, heartbeats will fail and eventually let you cease the execution of the application, as described in Heartbeats. Upon next checkout, the local grace license is activated in place of the network license for the permitted number of hours. If the license server comes up before the grace license expires, future checkout requests will acquire a network license as usual, but will not reset the expire time of the grace license.
To prevent fraud and over-licensing, LM-X does not allow the user to obtain a new grace license for 7 days after the expiration of the previously activated grace license. If the user needs a local license in the meantime, using borrow is suggested.
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Licensed applications must then enable grace licenses by calling calling LMX_SetOption(). See the "LMX_OPT_ALLOW_GRACE" description in LMX_SetOption.