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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hello,<o:p></o:p></p><p class=MsoNormal><o:p>&nbsp;</o:p></p><p class=MsoNormal>I have a basic question regarding the way drbd replication works.&nbsp; I am using drbd 8.3.8 to mirror a volume that I am exporting using IET iscsi-target.&nbsp; I am using protocol C and I have the iscsi-target exporting the volume using write-through IOMode.<o:p></o:p></p><p class=MsoNormal><o:p>&nbsp;</o:p></p><p class=MsoNormal>Can I safely enable write-back mode on the iscsi-target with DRBD?&nbsp; (independent of the inherent risks associated with write-back anyways, I have BBWC controller and UPS on server)<o:p></o:p></p><p class=MsoNormal><o:p>&nbsp;</o:p></p><p class=MsoNormal>Will the memory buffering of writes affect data integrity on the peer node? Should or can I use another DRBD protocol?<o:p></o:p></p><p class=MsoNormal><o:p>&nbsp;</o:p></p><p class=MsoNormal>I obviously am new to DRBD.&nbsp; Thanks in advance for the help.<o:p></o:p></p><p class=MsoNormal><o:p>&nbsp;</o:p></p><p class=MsoNormal><o:p>&nbsp;</o:p></p><p class=MsoNormal><b><span style='font-family:"Arial","sans-serif"'>Sean McCreadie<o:p></o:p></span></b></p><p class=MsoNormal><span style='font-family:"Arial","sans-serif"'>Systems Administrator<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Arial","sans-serif"'>Canyon Partners, LLC<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Arial","sans-serif"'>2000 Avenue of the Stars<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Arial","sans-serif"'>11th Floor<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Arial","sans-serif"'>Los Angeles, California 90067<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Arial","sans-serif"'>Direct:&nbsp; +1 (310) 272-1764<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Arial","sans-serif"'><a href="SMccreadie@CanyonPartners.com">SMccreadie@CanyonPartners.com</a><o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Arial","sans-serif"'><o:p>&nbsp;</o:p></span></p><p class=MsoNormal><o:p>&nbsp;</o:p></p><p class=MsoNormal><o:p>&nbsp;</o:p></p></div></body></html>