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This directive can be used only with network licenses; accordingly, the COUNT directive must be set if GRACE is set.
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Grace licenses work very similarly to license borrowing, described in BORROW. A temporary license is written at the client side upon each successful license checkout from a license server. This license is written in an inactivated state, so it does not have a fixed expiration date set.
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.