Selon Ling Hwa Hing <hwahing@xxxxxxxxxxxxx>: > hi, > I've got problem to use dmsetup. i read the documentation provided from > http://christophe.varoqui.free.fr/multipath.html, man dmsetup, intro and some > of the doc from google and the comments from the source code (can't > understand the code) > I still dont really understand how this low level settings can effect to the > multipath setup. > you don't need to use dmsetup if the multipath-tools work for you > I'm able to create a few device without using the table file. but dont know > how to use it. > dmsetup -j 8 -m 0 create impstor1 -u [uuid from uuidgen] --notable > the device node is store at the /dev/mapper/ > yes : no table, no i/o > i got no idea where to enter this entry like what describe in the website. > > 0 35258368 linear 8:48 65920 (I do not know where to get the target > parameters) > 35258368 35258368 linear 8:32 65920 > 70516736 17694720 linear 8:16 17694976 > 88211456 17694720 linear 8:16 256 > this is just an example, like I said, you don't need to play with that. in case you mind, though, here is how you can feed the tables : echo "0 27262976 multipath 2 round-robin 2 0 /dev/sda /dev/sdk round-robin 2 0 /dev/sdc /dev/sdm" | dmsetup create myfcdev > Here is an example of a multipath target : > 0 27262976 multipath 2 round-robin 2 0 /dev/sda /dev/sdk round-robin 2 0 > /dev/sdc /dev/sdm > good to see the tools work for you. there, after execing "multipath", you should have a /udev/$wwid created. you can format and play with that device node. > > I'm using emulex driver for lp8000 its connect to compaq san. 2 lp8000 > installed. > the box see 4 scsi drive sdc,sdd,sde,sdf. i can only use it as a md device. > with raidtab. > this SAN environment is tested and works ok with multipath-tools > i read the doc for many many times. sigh... i really dont know where to > start. and where to stop. > It seems you already got what you want : just verify you have that /udev/$wwid node. regards, cvaroqui
