This is a very common issue.  The vss-control volume is used by Microsoft.  When the array was set up a CHAP user ACL was assigned to it.   Vmware iSCSI logic believes that any discoverable volume can also be logged into.   However, since ESX isn't configured with that CHAP username password the iSCSI login fails.  It's trying to bypass the CHAP username / password, hence the "Security phase" error message.   In the EQL GUI, there's a checkbox under iSCSI tab, called "Discovery Filter"    The will prevent CHAP volumes from being discoverable in the future. Bad news is after setting that checkbox, you'll have to reboot your ESX servers to prevent them from continuing to try to log into that volume.   You can try going to Configuration->Storage Adapters->SW iSCSI adapter->Properties->Static Discovery and remove the vss-control volume from the list of discovered targets.   That might work.  A reboot after setting the filter definitely will. Regards,
 ERROR  2/1/12  2:39:10 PM  member1    iSCSI login to target '10.195.1.76:3260, iqn.2001-05.com.equallogic:0-8a0906-8b5a41509-50e0000000a4d354-vss-control' from initiator '10.195.1.86:53110, iqn.1998-01.com.vmware:srb001074-311ddf52' failed for the following reason:    Initiator tried to bypass the security phase but we cannot.       Please help...All of our servers are down right now...    
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