10.00 DMARC_REJECT for outging mail all of a sudden..
Posted: 07 Nov 2019 13:14
Yeah... something has gone wrong all of a sudden and I do not seem to be able to find the cause.
My mail filter has been running on Microsoft Hyper-Visor rather well for almost a year now. It sits in front of an hMail server and filters all inbound and outbound mail. Usual morning routine is to make sure all hosts inside the network are up to date including the mail filter. Saturday morning (11/2/2019) there were some OS updates to to the filter but before applying them I naturally created a checkpoint of the filter on the Hyper-Visor. Unfortunately these updates ended up breaking networking on the filter which in turn caused a few cascading issues. So.. I rolled back to the checkpoint to get the filter back up and running again. Incoming mail was still working perfectly, being analyzed and then sent on into the hMail server without issue. Outbound mail however is now being tagged as Spam and completely blocked due to DMARC_REJECT and I've been unable to figure out why.
I've checked all of the original configurations and everything seems to be in order. Internal domains and networks are correctly configured as they had been but any and all outbound mail is being blocked. If all else fails, I'll simply resort redeploying a fresh new EFA Project appliance on my VSphere server rather than the Hyper-Visor as it's easier to roll back without issue when something goes wrong (unlike Microsoft's Hyper-Visor).
Any suggestions on where to start looking to fix this before taking the above approach would be deeply appreciated.
My mail filter has been running on Microsoft Hyper-Visor rather well for almost a year now. It sits in front of an hMail server and filters all inbound and outbound mail. Usual morning routine is to make sure all hosts inside the network are up to date including the mail filter. Saturday morning (11/2/2019) there were some OS updates to to the filter but before applying them I naturally created a checkpoint of the filter on the Hyper-Visor. Unfortunately these updates ended up breaking networking on the filter which in turn caused a few cascading issues. So.. I rolled back to the checkpoint to get the filter back up and running again. Incoming mail was still working perfectly, being analyzed and then sent on into the hMail server without issue. Outbound mail however is now being tagged as Spam and completely blocked due to DMARC_REJECT and I've been unable to figure out why.
I've checked all of the original configurations and everything seems to be in order. Internal domains and networks are correctly configured as they had been but any and all outbound mail is being blocked. If all else fails, I'll simply resort redeploying a fresh new EFA Project appliance on my VSphere server rather than the Hyper-Visor as it's easier to roll back without issue when something goes wrong (unlike Microsoft's Hyper-Visor).
Any suggestions on where to start looking to fix this before taking the above approach would be deeply appreciated.