Date: Fri, 27 Nov 2015 12:08:26 -0600 From: Matthew Grooms <mgrooms@shrew.net> To: Willem Jan Withagen <wjw@digiware.nl>, freebsd-current@freebsd.org Subject: Re: Resizing a zpool as a VMware ESXi guest ... Message-ID: <56589C1A.1020702@shrew.net> In-Reply-To: <56581F5A.4010009@digiware.nl> References: <543841B8.4070007@shrew.net> <20141016081016.GA4670@brick.home> <5657F135.6080902@shrew.net> <56581F5A.4010009@digiware.nl>
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On 11/27/2015 3:16 AM, Willem Jan Withagen wrote: > On 27-11-2015 06:59, Matthew Grooms wrote: >> On 10/16/2014 3:10 AM, Edward Tomasz Napierała wrote: >>> On 1010T1529, Matthew Grooms wrote: >>>> All, >>>> >>>> I am a long time user and advocate of FreeBSD and manage a several >>>> deployments of FreeBSD in a few data centers. Now that these >>>> environments are almost always virtual, it would make sense that >>>> FreeBSD >>>> support for basic features such as dynamic disk resizing. It looks >>>> like >>>> most of the parts are intended to work. Kudos to the FreeBSD >>>> foundation >>>> for seeing the need and sponsoring dynamic increase of online UFS >>>> filesystems via growfs. Unfortunately, it would appear that there are >>>> still problems in this area, such as ... >>>> >>>> a) cam/geom recognizing when a drive's size has increased >>>> b) zpool recognizing when a gpt partition size has increased >>>> >>>> For example, if I do an install of FreeBSD 10 on VMware using ZFS, >>>> I see >>>> the following ... >>>> >>>> root@zpool-test:~ # gpart show >>>> => 34 16777149 da0 GPT (8.0G) >>>> 34 1024 1 freebsd-boot (512K) >>>> 1058 4194304 2 freebsd-swap (2.0G) >>>> 4195362 12581821 3 freebsd-zfs (6.0G) >>>> >>>> If I increase the VM disk size using VMware to 16G and rescan using >>>> camcontrol, this is what I see ... >>> "camcontrol rescan" does not force fetching the updated disk size. >>> AFAIK there is no way to do that. However, this should happen >>> automatically, if the "other side" properly sends proper Unit Attention >>> after resizing. No idea why this doesn't happen with VMWare. >>> Reboot obviously clears things up. >>> >>> [..] >>> >>>> Now I want the claim the additional 14 gigs of space for my zpool ... >>>> >>>> root@zpool-test:~ # zpool status >>>> pool: zroot >>>> state: ONLINE >>>> scan: none requested >>>> config: >>>> >>>> NAME STATE READ >>>> WRITE CKSUM >>>> zroot ONLINE 0 >>>> 0 0 >>>> gptid/352086bd-50b5-11e4-95b8-0050569b2a04 ONLINE 0 >>>> 0 0 >>>> >>>> root@zpool-test:~ # zpool set autoexpand=on zroot >>>> root@zpool-test:~ # zpool online -e zroot >>>> gptid/352086bd-50b5-11e4-95b8-0050569b2a04 >>>> root@zpool-test:~ # zpool list >>>> NAME SIZE ALLOC FREE CAP DEDUP HEALTH ALTROOT >>>> zroot 5.97G 876M 5.11G 14% 1.00x ONLINE - >>>> >>>> The zpool appears to still only have 5.11G free. Lets reboot and try >>>> again ... >>> Interesting. This used to work; actually either of those >>> (autoexpand or >>> online -e) should do the trick. >>> >>>> root@zpool-test:~ # zpool set autoexpand=on zroot >>>> root@zpool-test:~ # zpool online -e zroot >>>> gptid/352086bd-50b5-11e4-95b8-0050569b2a04 >>>> root@zpool-test:~ # zpool list >>>> NAME SIZE ALLOC FREE CAP DEDUP HEALTH ALTROOT >>>> zroot 14.0G 876M 13.1G 6% 1.00x ONLINE - >>>> >>>> Now I have 13.1G free. I can add this space to any of my zfs >>>> volumes and >>>> it picks the change up immediately. So the question remains, why do I >>>> need to reboot the OS twice to allocate new disk space to a volume? >>>> FreeBSD is first and foremost a server operating system. Servers are >>>> commonly deployed in data centers. Virtual environments are now >>>> commonplace in data centers, not the exception to the rule. VMware >>>> still >>>> has the vast majority of the private virutal environment market. I >>>> assume that most would expect things like this to work out of the box. >>>> Did I miss a required step or is this fixed in CURRENT? >>> Looks like genuine bugs (or rather, one missing feature and one bug). >>> Filling PRs for those might be a good idea. >>> >> >> All, >> >> I know this is a very late follow up, but spent some more time looking >> at this today and found some additional information that I found quite >> interesting. I setup two VMs, one that acts as an iSCSI initiator ( >> CURRENT ) and another that acts as a target ( 10.2-RELEASE ). Both are >> running under ESXi v5.5. There are two block devices on the initiator, >> da1 and da2, that I used for resize testing ... >> >> [root@iscsi-i /home/mgrooms]# camcontrol devlist >> <NECVMWar VMware IDE CDR10 1.00> at scbus1 target 0 lun 0 (cd0,pass0) >> <VMware Virtual disk 1.0> at scbus2 target 0 lun 0 (pass1,da0) >> <VMware Virtual disk 1.0> at scbus2 target 1 lun 0 (pass2,da1) >> <FREEBSD CTLDISK 0001> at scbus3 target 0 lun 0 (da2,pass3) >> >> The da1 device is a virtual disk hanging off of a VMware virtual SAS >> controller ... >> >> [root@iscsi-i /home/mgrooms]# pciconf >> ... >> mpt0@pci0:3:0:0: class=0x010700 card=0x197615ad chip=0x00541000 >> rev=0x01 hdr=0x00 >> vendor = 'LSI Logic / Symbios Logic' >> device = 'SAS1068 PCI-X Fusion-MPT SAS' >> class = mass storage >> subclass = SAS >> >> [root@iscsi-i /home/mgrooms]# camcontrol readcap da1 -h >> Device Size: 10 G, Block Length: 512 bytes >> >> [root@iscsi-i /home/mgrooms]# gpart show da1 >> => 40 20971440 da1 GPT (10G) >> 40 20971440 1 freebsd-ufs (10G) >> >> The da2 device is an iSCSI LUN mounted from my FreeBSD 10.2 VM running >> ctld ... >> >> [root@iscsi-i /home/mgrooms]# iscsictl >> Target name Target portal State >> iqn.2015-01.lab.shrew:target0 iscsi-t.shrew.lab Connected: da2 >> >> [root@iscsi-i /home/mgrooms]# camcontrol readcap da2 -h >> Device Size: 10 G, Block Length: 512 bytes >> >> [root@iscsi-i /home/mgrooms]# gpart show da2 >> => 40 20971440 da2 GPT (10G) >> 40 24 - free - (12K) >> 64 20971392 1 freebsd-ufs (10G) >> 20971456 24 - free - (12K) >> >> When I increased the size of da1 ( the VMDK ) and then re-ran >> 'camcontrol readcap' without a reboot, it clearly showed that the disk >> size had increased. However, geom failed to recognize the additional >> capacity ... >> >> [root@iscsi-i /home/mgrooms]# camcontrol readcap da1 -h >> Device Size: 16 G, Block Length: 512 bytes >> >> [root@iscsi-i /home/mgrooms]# gpart show da1 >> => 40 20971440 da1 GPT (10G) >> 40 20971440 1 freebsd-ufs (10G) >> >> Here is the interesting bit. I increased the size of da2 by modifying >> the lun size in ctld.conf on the target and then issued a /etc/rd.d/ctld >> reload. When I re-ran 'camcontrol readcap' on the initiator without a >> reboot, it also showed that the disk size had increased, but this time >> geom recognized the additional capacity as well ... >> >> [root@iscsi-i /home/mgrooms]# camcontrol readcap da2 -h >> Device Size: 16 G, Block Length: 512 bytes >> >> [root@iscsi-i /home/mgrooms]# gpart show da2 >> => 40 33554352 da2 GPT (16G) >> 40 24 - free - (12K) >> 64 20971392 1 freebsd-ufs (10G) >> 20971456 12582936 - free - (6.0G) >> >> I was then able to resize the partition and then grow the UFS >> filesystem, all without rebooting the VM ... >> >> [root@iscsi-i /home/mgrooms]# gpart resize -i 1 da2 >> da2p1 resized >> >> [root@iscsi-i /home/mgrooms]# gpart show da2 >> => 40 33554352 da2 GPT (16G) >> 40 24 - free - (12K) >> 64 33554304 1 freebsd-ufs (16G) >> 33554368 24 - free - (12K) >> >> [root@iscsi-i /home/mgrooms]# growfs da2p1 >> Device is mounted read-write; resizing will result in temporary write >> suspension for /var/data2. >> It's strongly recommended to make a backup before growing the file >> system. >> OK to grow filesystem on /dev/da2p1, mounted on /var/data2, from 10GB to >> 16GB? [Yes/No] Yes >> super-block backups (for fsck_ffs -b #) at: >> 21798272, 23080512, 24362752, 25644992, 26927232, 28209472, 29491712, >> 30773952, 32056192, 33338432 >> >> [root@iscsi-i /home/mgrooms]# df -h >> Filesystem Size Used Avail Capacity Mounted on >> /dev/da0p3 15G 1.2G 12G 9% / >> devfs 1.0K 1.0K 0B 100% /dev >> /dev/da1p1 9.7G 32M 8.9G 0% /var/data1 >> /dev/da2p1 15G 32M 14G 0% /var/data2 >> >> It's also worth noting that the additional space was not recognized by >> gpart/geom on the initiator until after the 'camcontrol readcap da2' >> command was run. In other words, I'm skeptical that it was a Unit >> Attention notification that made the right thing happen since it still >> took manual prodding of cam to get the new disk geometry up into the >> geom layer. > > I remember doing this for a bhyve VM, and had the type same problem. > Getting gpart in the VM to actually pickup the new size required some > extra prodding (I like that word) or rebooting the VM. > I can remember reporting this: > tpoic: "resampeling of a ZVOL that has been resized" > and getting a fix from Andrey V. Elsukov... > > Index: head/sys/geom/part/g_part_gpt.c > =================================================================== > --- head/sys/geom/part/g_part_gpt.c (revision 282044) > +++ head/sys/geom/part/g_part_gpt.c (working copy) > @@ -760,7 +760,7 @@ g_part_gpt_resize(struct g_part_table *basetable, > struct g_part_gpt_entry *entry; > > if (baseentry == NULL) > - return (EOPNOTSUPP); > + return (g_part_gpt_recover(basetable)); > > entry = (struct g_part_gpt_entry *)baseentry; > baseentry->gpe_end = baseentry->gpe_start + gpp->gpp_size - 1; > > Which went into the tree, but perhaps only in HEAD. > And that helped me getting the correct retasting of the GPART partitions. > > Not sure if this snippet would help you to get around GEOM tasting the > new size. > Thanks for the response. I read the commit logs daily but I don't recall that one. However, it looks like that change went in over five months ago ( r284151 ) and I'm running these tests on a CURRENT ... [mgrooms@iscsi-i ~]$ uname -a FreeBSD iscsi-i.shrew.lab 11.0-CURRENT FreeBSD 11.0-CURRENT #0 r291085: Thu Nov 19 21:48:13 UTC 2015 root@releng2.nyi.freebsd.org:/usr/obj/usr/src/sys/GENERIC amd64 Something else is amiss here and I don't have the chops to fix it myself. I tried compiling a custom kernel with CAMDEBUG and twiddling with the camcontrol debug options to compare the output during the VMDK vs iSCSI disk resize process. Nothing was obvious to my untrained eye. I'd be more than happy to test patches or provide additional information to anyone willing to help. Thanks, -Matthew
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