The IPsec status information of a network is as follows, [USG A] display ike sa
current ike sa number: 2
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conn-id peer flag phase vpn
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40006 <unnamed> NONE v1:2 public
40004 1.1.1.2 RD|ST v1:2 public
2012-08-08 15:05:15 USG %%01IKE/4/WARNING (I): phase2: proposal or pfs dh-group up mismatch, please check ipsec proposal and pfs dh-group configuration.
*0.1921499990 USG IKE/7/DEBUG: got NOTIFY of type NO_PROPOSAL_CHOSEN
Which of the following options is a possible cause of failure?