[ceph-users] blockdev --setro cannot set krbd to readonly

I mapped an image to a system, and used blockdev to make it readonly. But it failed.[root@ceph0 mnt]# blockdev --setro /dev/rbd2[root@ceph0 mnt]# blockdev --getro /dev/rbd20 It's on Centos6.4 with kernel 3.10.6 .Ceph 0.61.8 . Any idea?

[ceph-users] System reboot hangs when umounting filesystem on rbd

Centos 6.4Kernel 3.10.6Ceph 0.61.8 My ceph cluster is deployed on three nodes.One rbd image was created, mapped to one of the three nodes, formatted with ext4, and mounted.When rebooting this node, it hung umouting the file system on the rbd. My guess about the root cause:When the system

[ceph-users] How to force a monitor time check?

Time skews happen frequently when the systems running monitors are restarted.With ntp server configured, the time skew between systems will be fixed over some time. But the ceph monitors won't find it at once if there are no time check messages at that time, so the ceph status will be still

Re: [ceph-users] Is it possible to change the pg number after adding new osds?

[mailto:ceph-users-boun...@lists.ceph.com] On Behalf Of Da Chun Ng Sent: Montag, 2. September 2013 04:49 To: ceph-users@lists.ceph.com Subject: [ceph-users] Is it possible to change the pg number after adding new osds? According to the doc, the pg numbers should be enlarged for better read/write

[ceph-users] Is it possible to change the pg number after adding new osds?

According to the doc, the pg numbers should be enlarged for better read/write balance if the osd number is increased.But seems the pg number cannot be changed on the fly. It's fixed when the pool is created. Am I right?

[ceph-users] The whole cluster hangs when changing MTU to 9216

Centos 6.4Ceph Cuttlefish 0.61.7, or 0.61.8. I changed the MTU to 9216(or 9000), then restarted all the cluster nodes. The whole cluster hung, with messages in the mon log as below:4048 2013-08-26 15:52:43.028554 7fd83f131700 1 mon.ceph0@0(electing).elector(15) init, last seen epoch 154049

Re: [ceph-users] Poor write/random read/random write performance

CC: ceph-users@lists.ceph.com Subject: Re: [ceph-users] Poor write/random read/random write performance On 08/19/2013 12:05 PM, Da Chun Ng wrote: Thank you! Testing now. How about pg num? I'm using the default size 64, as I tried with (100 * osd_num)/replica_size, but it decreased

[ceph-users] Poor write/random read/random write performance

I have a 3 nodes, 15 osds ceph cluster setup:* 15 7200 RPM SATA disks, 5 for each node.* 10G network* Intel(R) Xeon(R) CPU E5-2620(6 cores) 2.00GHz, for each node.* 64G Ram for each node. I deployed the cluster with ceph-deploy, and created a new data pool for cephfs.Both the data and metadata

Re: [ceph-users] Poor write/random read/random write performance

Sorry, forget to tell the OS and kernel version. It's Centos 6.4 with kernel 3.10.6 .fio 2.0.13 . From: dachun...@outlook.com To: ceph-users@lists.ceph.com Date: Mon, 19 Aug 2013 11:28:24 + Subject: [ceph-users] Poor write/random read/random write performance I have a 3 nodes, 15 osds

Re: [ceph-users] Poor write/random read/random write performance

] Poor write/random read/random write performance On 08/19/2013 06:28 AM, Da Chun Ng wrote: I have a 3 nodes, 15 osds ceph cluster setup: * 15 7200 RPM SATA disks, 5 for each node. * 10G network * Intel(R) Xeon(R) CPU E5-2620(6

Re: [ceph-users] Poor write/random read/random write performance

Subject: Re: [ceph-users] Poor write/random read/random write performance On 08/19/2013 08:59 AM, Da Chun Ng wrote: Thanks very much! Mark. Yes, I put the data and journal on the same disk, no SSD in my environment. My controllers are general SATA II. Ok, so in this case the lack of WB