On Thu, 19 Jun 2008 13:54:15 +0200 Tomasz Chmielewski <mangoo at wpkg.org> wrote: > Is there a way to disable write caching when using tgtd as a target? > > Right now, it seems to be impossible (at least I didn't find an option > in documentation nor sources) and setting it on the initiator fails: > > initiator# sdparm /dev/sda > /dev/sda: IET VIRTUAL-DISK 0001 > Caching (SBC) mode page: > WCE 1 [cha: y, def: 1, sav: 1] > RCD 0 [cha: n, def: 0, sav: 0] > (...) > > initiator# sdparm --set WCE=0 /dev/sda > /dev/sda: IET VIRTUAL-DISK 0001 > change_mode_page: failed setting page: Caching (SBC) I've uploaded two patches: http://stgt.berlios.de/patches/0001-iscsi-fix-sense-handling.patch http://stgt.berlios.de/patches/0002-sbc-add-WCE-support-to-bs_rdwr.patch With the patches, you can disable write caching in the following way: tgtadm --lld iscsi --op update --mode logicalunit --tid 1 --lun 1 --params mode_page=8:0:18:0x10:0:0xff:0xff:0:0:0xff:0xff:0xff:0xff:0x80:0x14:0:0:0:0:0:0 Note that you need to modify tid and lun in your environment. Shortly, I'll let you control write caching via sdparm too. |