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<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Cambria",serif;color:blue">Hi,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Cambria",serif;color:blue"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Cambria",serif;color:blue">I am facing a weird behaviour in strongSwan version 4.3.6, where there are multiple(2) IKE_SAs getting created for the same tunnel as soon as I start a bi-directional
traffic.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Cambria",serif;color:blue"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Cambria",serif;color:blue">peer1--------------------peer2<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Cambria",serif;color:blue">IKE version: 2<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Cambria",serif;color:blue">IKE Lifetime: 24Hrs<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Cambria",serif;color:blue">Lifetime: 12Hrs<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Cambria",serif;color:blue">DPD action: restart<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Cambria",serif;color:blue"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Cambria",serif;color:blue">From the logs I could see that the peer1 is initiating an IKE_SA, parameters are negotiated and one set of IKE_SA and IPSEC_SAs are formed. Within a short duration peer2
requests for a connection(not sure why this is happening) and another set of IKE_SA and IPSEC_SAs are getting established.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Cambria",serif;color:blue"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Cambria",serif;color:blue">After this DPD is active and it fails to get DPD response, after 5 retransmits it restarts the SAs and now another set of IKE and IPSEC_SAs get established and this continues
to have a large number of IPSec SAs built up after sometime.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Cambria",serif;color:blue;mso-fareast-language:EN-IN"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Cambria",serif;color:blue;mso-fareast-language:EN-IN">Can anyone explain what is happening here?
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Cambria",serif;color:blue;mso-fareast-language:EN-IN">How can there be new IKE SA, getting established successfully for same connection before the existing one expires?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Cambria",serif;color:blue;mso-fareast-language:EN-IN"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Cambria",serif;color:blue;mso-fareast-language:EN-IN">Also, given that is possible, shouldn’t the peer respond to DPD requests of both the IKE_SAs(or all IKE SPIs on that connection)?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Cambria",serif;color:blue;mso-fareast-language:EN-IN"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Cambria",serif;color:blue;mso-fareast-language:EN-IN">Thanks,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Cambria",serif;color:blue;mso-fareast-language:EN-IN">Harsha<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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