Dear all,<br><div class="gmail_quote"><div><br></div><div>I have sent this problem earlier but maybe its not detail, here I try to write more detail. I hope anybody can help me to point out the problem.</div><div>First of all used virtualization, I used Ubuntu 12.04 x64 both for domain0 and domainU with modification to run under xen hypervisor and work with remus.</div>

<div>I follow and configured the remus with this notes <a href="http://wiki.xen.org/wiki/Install_Xen_4.1.4_with_Remus_and_DRBD_on_Ubuntu_12.10" target="_blank">http://wiki.xen.org/wiki/Install_Xen_4.1.4_with_Remus_and_DRBD_on_Ubuntu_12.10</a> but I used xen 4.2.2 as my hypervisor with DRBD 3.8.11 remus support from this link <span style="background-color:rgb(249,249,249);line-height:1.3em"><a href="http://remusha.wikidot.com/local--files/configuring-and-installing-remus/drbd-8.3.11-remus.tar.gz" target="_blank">http://remusha.wikidot.com/local--files/configuring-and-installing-remus/drbd-8.3.11-remus.tar.gz</a>.</span></div>

<div><span style="background-color:rgb(249,249,249);line-height:1.3em"><br></span></div><div><span style="line-height:16.890625px">If DRBD run with Primary - secondary mode, there is no problem. However remus run with dual primary mode. If I try to run remus the drbd will freeze and cause my domainU to freeze. With dmesg error message is below :</span></div>

<div><span style="line-height:16.890625px"><br></span></div><div><div><span style="line-height:16.890625px">[242525.600067] block drbd1: Local backing block device frozen?</span></div><div><span style="line-height:16.890625px">[242537.632070] block drbd1: Local backing block device frozen?</span></div>

<div><span style="line-height:16.890625px">[242549.664075] block drbd1: Local backing block device frozen?</span></div><div><span style="line-height:16.890625px">[242561.696083] block drbd1: Local backing block device frozen?</span></div>

<div><span style="line-height:16.890625px">[242573.728079] block drbd1: Local backing block device frozen?</span></div><div><span style="line-height:16.890625px">[242585.760069] block drbd1: Local backing block device frozen?</span></div>

<div><span style="line-height:16.890625px">[242597.792079] block drbd1: Local backing block device frozen?</span></div><div><span style="line-height:16.890625px">[242609.824069] block drbd1: Local backing block device frozen?</span></div>

<div><span style="line-height:16.890625px">[242621.856083] block drbd1: Local backing block device frozen?</span></div><div><span style="line-height:16.890625px">[242633.888068] block drbd1: Local backing block device frozen?</span></div>

<div><span style="line-height:16.890625px">[242640.332124] INFO: task blkback.2.xvda:5779 blocked for more than 120 seconds.</span></div><div><span style="line-height:16.890625px">[242640.332130] &quot;echo 0 &gt; /proc/sys/kernel/hung_task_timeout_secs&quot; disables this message.</span></div>

<div><span style="line-height:16.890625px">[242640.332134] blkback.2.xvda  D ffff88003fc13780     0  5779      2 0x00000000</span></div><div><span style="line-height:16.890625px">[242640.332142]  ffff880026743940 0000000000000246 000000000000000b ffff8800267402d0</span></div>

<div><span style="line-height:16.890625px">[242640.332150]  ffff880026743fd8 ffff880026743fd8 ffff880026743fd8 0000000000013780</span></div><div><span style="line-height:16.890625px">[242640.332157]  ffff880032944500 ffff88003368c500 ffff8800357d6000 ffff8800357d69d8</span></div>

<div><span style="line-height:16.890625px">[242640.332164] Call Trace:</span></div><div><span style="line-height:16.890625px">[242640.332178]  [&lt;ffffffff816579cf&gt;] schedule+0x3f/0x60</span></div><div><span style="line-height:16.890625px">[242640.332200]  [&lt;ffffffffa00e68d5&gt;] drbd_al_begin_io+0x205/0x270 [drbd]</span></div>

<div><span style="line-height:16.890625px">[242640.332207]  [&lt;ffffffff811adde8&gt;] ? bvec_alloc_bs+0x68/0x100</span></div><div><span style="line-height:16.890625px">[242640.332212]  [&lt;ffffffff811adf32&gt;] ? bio_alloc_bioset+0xb2/0xf0</span></div>

<div><span style="line-height:16.890625px">[242640.332219]  [&lt;ffffffff8108aa50&gt;] ? add_wait_queue+0x60/0x60</span></div><div><span style="line-height:16.890625px">[242640.332231]  [&lt;ffffffffa00e41bd&gt;] drbd_make_request_common+0xc4d/0x1430 [drbd]</span></div>

<div><span style="line-height:16.890625px">[242640.332239]  [&lt;ffffffffa01b83ce&gt;] ? xen_blkbk_map+0x24e/0x2f0 [xen_blkback]</span></div><div><span style="line-height:16.890625px">[242640.332245]  [&lt;ffffffff81301006&gt;] ? throtl_find_tg+0x46/0x60</span></div>

<div><span style="line-height:16.890625px">[242640.332257]  [&lt;ffffffffa00e4e04&gt;] drbd_make_request+0x464/0x7e0 [drbd]</span></div><div><span style="line-height:16.890625px">[242640.332264]  [&lt;ffffffff812f03bb&gt;] ? generic_make_request_checks+0x1eb/0x370</span></div>

<div><span style="line-height:16.890625px">[242640.332269]  [&lt;ffffffff812f0194&gt;] generic_make_request.part.50+0x74/0xb0</span></div><div><span style="line-height:16.890625px">[242640.332274]  [&lt;ffffffff812f05a8&gt;] generic_make_request+0x68/0x70</span></div>

<div><span style="line-height:16.890625px">[242640.332278]  [&lt;ffffffff812f0635&gt;] submit_bio+0x85/0x110</span></div><div><span style="line-height:16.890625px">[242640.332284]  [&lt;ffffffffa01b8f0f&gt;] dispatch_rw_block_io+0x44f/0x700 [xen_blkback]</span></div>

<div><span style="line-height:16.890625px">[242640.332292]  [&lt;ffffffff8100330e&gt;] ? xen_end_context_switch+0x1e/0x30</span></div><div><span style="line-height:16.890625px">[242640.332298]  [&lt;ffffffffa01b93df&gt;] __do_block_io_op+0x21f/0x360 [xen_blkback]</span></div>

<div><span style="line-height:16.890625px">[242640.332304]  [&lt;ffffffffa01b9608&gt;] xen_blkif_schedule+0xb8/0x320 [xen_blkback]</span></div><div><span style="line-height:16.890625px">[242640.332309]  [&lt;ffffffff8108aa50&gt;] ? add_wait_queue+0x60/0x60</span></div>

<div><span style="line-height:16.890625px">[242640.332314]  [&lt;ffffffffa01b9550&gt;] ? xen_blkif_be_int+0x30/0x30 [xen_blkback]</span></div><div><span style="line-height:16.890625px">[242640.332319]  [&lt;ffffffff81089fbc&gt;] kthread+0x8c/0xa0</span></div>

<div><span style="line-height:16.890625px">[242640.332326]  [&lt;ffffffff81664034&gt;] kernel_thread_helper+0x4/0x10</span></div><div><span style="line-height:16.890625px">[242640.332330]  [&lt;ffffffff816620e3&gt;] ? int_ret_from_sys_call+0x7/0x1b</span></div>

<div><span style="line-height:16.890625px">[242640.332336]  [&lt;ffffffff81659dbc&gt;] ? retint_restore_args+0x5/0x6</span></div><div><span style="line-height:16.890625px">[242640.332340]  [&lt;ffffffff81664030&gt;] ? gs_change+0x13/0x13</span></div>

<div><span style="line-height:16.890625px">[242645.920070] block drbd1: Local backing block device frozen?</span></div><div><span style="line-height:16.890625px">[242657.952074] block drbd1: Local backing block device frozen?</span></div>

<div><span style="line-height:16.890625px">[242669.984072] block drbd1: Local backing block device frozen?</span></div><div><span style="line-height:16.890625px">[242682.016071] block drbd1: Local backing block device frozen?</span></div>

<div><span style="line-height:16.890625px">[242694.048071] block drbd1: Local backing block device frozen?</span></div><div><span style="line-height:16.890625px">[242706.080071] block drbd1: Local backing block device frozen?</span></div>

<div><span style="line-height:16.890625px">[242718.112077] block drbd1: Local backing block device frozen?</span></div><div><span style="line-height:16.890625px">sb-voip2@sbvoip2:~$ sudo cat /proc/drbd</span></div><div><span style="line-height:16.890625px">version: 8.3.11 (api:88/proto:86-96)</span></div>

<div><span style="line-height:16.890625px">GIT-hash: 0de839cee13a4160eed6037c4bddd066645e23c5 build by root@sbvoip2, 2013-02-19 08:30:51</span></div><div><span style="line-height:16.890625px"><br></span></div><div><span style="line-height:16.890625px"> 1: cs:Connected ro:Primary/Primary ds:UpToDate/UpToDate D r-----</span></div>

<div><span style="line-height:16.890625px">    ns:14732 nr:1784712 dw:1799444 dr:579340 al:31 bm:44 lo:1 pe:0 ua:0 ap:1 ep:1 wo:b def:0 chkpt:662 oos:0</span></div><div style="line-height:16.890625px"><br></div></div><div style="line-height:16.890625px">

As we can read after drbd block device frozen then blkback also not working </div><div style="line-height:16.890625px"><br></div><div style="line-height:16.890625px">[242640.332124] INFO: task blkback.2.xvda:5779 blocked for more than 120 seconds.</div>

<div style="line-height:16.890625px"><br></div><div style="line-height:16.890625px">Some one told me its because high load of IO but I alwasy monitor my server with xm top and the serer load always under 50%</div><div style="line-height:16.890625px">

I hope anybody can help me, if you need some more log I will try to post it.</div><div style="line-height:16.890625px"><br></div><div style="line-height:16.890625px"><span style="color:rgb(34,34,34);line-height:19px;text-align:justify"> </span>However I found this patch <a href="http://permalink.gmane.org/gmane.linux.kernel.commits.head/358143">http://permalink.gmane.org/gmane.linux.kernel.commits.head/358143</a>, but I am not sure it could be applied with my DRBD version since I can&#39;t find <span style="color:rgb(34,34,34);line-height:19px;text-align:justify">drivers/block/drbd/drbd_state.c within my installation </span></div>
<div style="line-height:16.890625px"><br></div><div style="line-height:16.890625px">Many thanks,</div><div style="line-height:16.890625px">
<br></div><div style="line-height:16.890625px">Agya</div>
</div><br>