|
Hi Gregory, Thanks for the direction that I finish with 3 different rule in a ruleset for different rep size: Tested no bad-mapping and host / osd are correctly balanced between 2 chassis. Not sure if it can be optimized but I am happy with current result: rule rule_rep2 { ruleset 0 type replicated min_size 2 max_size 2 step take chassis1 step chooseleaf firstn 1 type host step emit step take chassis2 step chooseleaf firstn 1 type host step emit } rule rule_rep34 { ruleset 0 type replicated min_size 3 max_size 4 step take default step choose firstn 2 type chassis step chooseleaf firstn 2 type host step emit } rule rule_rep56 { ruleset 0 type replicated min_size 5 max_size 6 step take default step choose firstn 3 type chassis step chooseleaf firstn 3 type host step emit } Luke From: Gregory Farnum [mailto:greg@xxxxxxxxxxx]
With sufficiently new CRUSH versions (all the latest point releases on LTS?) I think you can simply have the rule return extra IDs which are dropped if they exceed the number required. So you can choose two chassis, then have those both
choose to lead OSDs, and return those 4 from the rule. On Fri, Feb 13, 2015 at 6:13 AM Luke Kao <Luke.Kao@xxxxxxxxxxxxx> wrote: Dear cepher, Currently I am working on crushmap to try to make sure the at least one copy are going to different chassis. Say chassis1 has host1,host2,host3, and chassis2 has host4,host5,host6. With replication =2, it’s not a problem, I can use the following step in rule step take chasses1 step chooseleaf firstn 1 type host step emit step take chasses2 step chooseleaf firstn 1 type host step emit But for replication=3, I tried
step take chasses1 step chooseleaf firstn 1 type host step emit step take chasses2 step chooseleaf firstn 1 type host step emit step take default step chooseleaf firstn 1 type host step emit At the end, the 3rd osd returned in rule test is always duplicate with first 1 or first 2. Any idea or what’s the direction to move forward? Thanks in advance BR, Luke MYCOM-OSI
_______________________________________________ This electronic message contains information from Mycom which may be privileged or confidential. The information is intended to be for the use of the individual(s) or entity named above. If you are not the intended recipient, be aware that any disclosure, copying, distribution or any other use of the contents of this information is prohibited. If you have received this electronic message in error, please notify us by post or telephone (to the numbers or correspondence address above) or by email (at the email address above) immediately. |
_______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
