Re: Creating root LVM
It depends on what you consider to be the bigger problem. A) having to care upfront about what needs space where is hard. Make / one huge logical volume and don't worry about space until you need more, then just grow / online. B) fixing a machine that won't boot is hard. When /'s contents are smeared across multiple devices it is tough to get the machine to a working state again, often requiring the service of a dedicated emergency rescue system. Note that this is further complicated by cloud management tools that impose their own restrictions on system disk layouts. It seems like no matter what you prefer, your cloud tools won't handle your chosen file system layout unless you like one big vanilla / partition with ext3 and no lvm at all. On Tue, Aug 23, 2016, 13:26 Donald Russell wrote: > We have rhel5 with rootvg and rootlv. That caused us some grief when a root > password was lost and we "simply wanted to mount it on another system". > Not so fast there skippy, all the systems have rootvg/lv so we had to work > around that... (Not rocket science, but inconvenient) > > Now, (upgrading to rehl7) we put the "basic Linux system" on a > simple-to-use Mod-9 and use LVM for application file systems and a few > others. Now it's very simple to mount that / file system on another server > if necessary. > > > > > > On Tuesday, August 23, 2016, Michael Weiner > wrote: > > > Good morning all, > > > > I was having a little debate yesterday and I want to get the experts on > > this list opinions. > > > > What's the best practice when it comes to the root directory? > > > > Is it acceptable and recommend to create an vgroot and lvroot so it is > > expandable? > > > > Or is it recommended to have the root directory as a regular directory > and > > not expandable. > > > > Thank you! > > > > > > Sent from my iPhone > > > > > > Sent from my iPhone > > -- > > For LINUX-390 subscribe / signoff / archive access instructions, > > send email to lists...@vm.marist.edu with the message: > > INFO LINUX-390 or visit > > http://www.marist.edu/htbin/wlvindex?LINUX-390 > > -- > > For more information on Linux on System z, visit > > http://wiki.linuxvm.org/ > > > > > -- > Sent from iPhone Gmail Mobile > > -- > For LINUX-390 subscribe / signoff / archive access instructions, > send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or > visit > http://www.marist.edu/htbin/wlvindex?LINUX-390 > -- > For more information on Linux on System z, visit > http://wiki.linuxvm.org/ > -- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 -- For more information on Linux on System z, visit http://wiki.linuxvm.org/
Re: Creating root LVM
We have rhel5 with rootvg and rootlv. That caused us some grief when a root password was lost and we "simply wanted to mount it on another system". Not so fast there skippy, all the systems have rootvg/lv so we had to work around that... (Not rocket science, but inconvenient) Now, (upgrading to rehl7) we put the "basic Linux system" on a simple-to-use Mod-9 and use LVM for application file systems and a few others. Now it's very simple to mount that / file system on another server if necessary. On Tuesday, August 23, 2016, Michael Weiner wrote: > Good morning all, > > I was having a little debate yesterday and I want to get the experts on > this list opinions. > > What's the best practice when it comes to the root directory? > > Is it acceptable and recommend to create an vgroot and lvroot so it is > expandable? > > Or is it recommended to have the root directory as a regular directory and > not expandable. > > Thank you! > > > Sent from my iPhone > > > Sent from my iPhone > -- > For LINUX-390 subscribe / signoff / archive access instructions, > send email to lists...@vm.marist.edu with the message: > INFO LINUX-390 or visit > http://www.marist.edu/htbin/wlvindex?LINUX-390 > -- > For more information on Linux on System z, visit > http://wiki.linuxvm.org/ > -- Sent from iPhone Gmail Mobile -- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 -- For more information on Linux on System z, visit http://wiki.linuxvm.org/
Re: Creating root LVM
I don't know if that changed but it used to be that zipl could safely boot from LVM that was on only one physical volume. See this older discussion for details: http://www.mail-archive.com/linux-390%40vm.marist.edu/msg62491.html Tomas Tomas Pavelka CA Technologies Sr Software Engineer CA CZ, s.r.o V Parku 12, 148 00 Praha Czech Republic Office: +25996 | tomas.pave...@ca.com Id. Císlo 25694073, z obchodního rejstříku, vedeného Městským soudem v Praze, oddíl C, vložka 61808 / Id. No. 25694073, registered in the Commercial Register maintained by the Municipal Court in Praque, Section C, File 61808 -- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 -- For more information on Linux on System z, visit http://wiki.linuxvm.org/
Re: Creating root LVM
>>> On 8/23/2016 at 08:18 AM, Michael Weiner wrote: -snip- > Is it acceptable and recommend to create an vgroot and lvroot so it is > expandable? It's acceptable, barely. I would never recommend it. It's caused me too much grief over the years. When you get thrown into a rescue situation, the only tools you have available are in the root file system. If you can't get to them because LVM is bent then you have to resort to other means, with the attendant problems others have already discussed. > Or is it recommended to have the root directory as a regular directory and > not expandable. This is what I recommend. If you break out the parts of the root file system that are likely to need expansion, / itself will never need to be expanded. Problem solved. Mark Post -- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 -- For more information on Linux on System z, visit http://wiki.linuxvm.org/
Re: Creating root LVM
The experts also still debate this .. I myself see nothing wrong with root in an LVM - others shudder in horror. There are pros and cons to both approaches. For recovery - having a bootable LVM free Linux is a good thing so you can mount other guests VG disks without worry of duplicate VGs.It's also helpful to use minidisk addresses to help identify VG 'parts'.. 2xx disks for root VG, 3xx disks for app VG, etc... just makes it easier to know what to link to see another guests VGs (helpful whether using root in LVM or not). Scott Rohling On Tue, Aug 23, 2016 at 5:18 AM, Michael Weiner wrote: > Good morning all, > > I was having a little debate yesterday and I want to get the experts on > this list opinions. > > What's the best practice when it comes to the root directory? > > Is it acceptable and recommend to create an vgroot and lvroot so it is > expandable? > > Or is it recommended to have the root directory as a regular directory and > not expandable. > > Thank you! > > > Sent from my iPhone > > > Sent from my iPhone > -- > For LINUX-390 subscribe / signoff / archive access instructions, > send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or > visit > http://www.marist.edu/htbin/wlvindex?LINUX-390 > -- > For more information on Linux on System z, visit > http://wiki.linuxvm.org/ > -- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 -- For more information on Linux on System z, visit http://wiki.linuxvm.org/
Re: Creating root LVM
Keep in mind that LVM's are unique to a Linux guest. If a volume is to be mounted in another system then it can't when an LVM with the same name already exists. Our cloning procedures want to mount a new system in our maintenance Linux guest. This means that the base system (at least /, /etc and /var) cannot live in an LVM. If it was we would get duplicate LVM names. That would make that cloning procedure more difficult, and (emergency) maintenance as well. Last month I had to copy data from an old guest to the new machine. Unfortunately part of the user data was created in an lv within the rootvg group. When I tried to mount that old data it failed because the rootvg was already online in the new machine. That rootvg normally only contains /var, opt, /usr and such. I don't particularly like the base system in LVM, because of the above mentioned reason. On the other hand, it does make it easier to expand filesystems, /usr for example. Met vriendelijke groet/With kind regards/Mit freundlichen Grüßen, Berry van Sleeuwen -Original Message- From: Linux on 390 Port [mailto:LINUX-390@VM.MARIST.EDU] On Behalf Of Michael Weiner Sent: Tuesday, August 23, 2016 2:18 PM To: LINUX-390@VM.MARIST.EDU Subject: Creating root LVM Good morning all, I was having a little debate yesterday and I want to get the experts on this list opinions. What's the best practice when it comes to the root directory? Is it acceptable and recommend to create an vgroot and lvroot so it is expandable? Or is it recommended to have the root directory as a regular directory and not expandable. Thank you! Sent from my iPhone Sent from my iPhone -- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 -- For more information on Linux on System z, visit http://wiki.linuxvm.org/ This e-mail and the documents attached are confidential and intended solely for the addressee; it may also be privileged. If you receive this e-mail in error, please notify the sender immediately and destroy it. As its integrity cannot be secured on the Internet, Atos’ liability cannot be triggered for the message content. Although the sender endeavours to maintain a computer virus-free network, the sender does not warrant that this transmission is virus-free and will not be liable for any damages resulting from any virus transmitted. On all offers and agreements under which Atos Nederland B.V. supplies goods and/or services of whatever nature, the Terms of Delivery from Atos Nederland B.V. exclusively apply. The Terms of Delivery shall be promptly submitted to you on your request.
Re: Creating root LVM
Yes I am referring to / yes. Is there any issues with using a vg or lv on /? Sent from my iPhone > On Aug 23, 2016, at 08:39, Michael MacIsaac wrote: > > Michael, > > When you say 'root directory' I assume you mean / and not /root/. > > FWIW, the only time we use LVMs is for application data or log files in > directories such as /opt/was/, /oradata/logs/ or something like that. We > used to use an LVM for /var/ but found we didn't need it. > > We use about a 12 GB file system for Linux (/). If the users fill up > regular Linux directories, the answer is 'Stop doing that', and very rarely > do they. > > Hope this helps. > >-Mike MacIsaac > > On Tue, Aug 23, 2016 at 8:18 AM, Michael Weiner > wrote: > >> Good morning all, >> >> I was having a little debate yesterday and I want to get the experts on >> this list opinions. >> >> What's the best practice when it comes to the root directory? >> >> Is it acceptable and recommend to create an vgroot and lvroot so it is >> expandable? >> >> Or is it recommended to have the root directory as a regular directory and >> not expandable. >> >> Thank you! >> >> >> Sent from my iPhone >> >> >> Sent from my iPhone >> -- >> For LINUX-390 subscribe / signoff / archive access instructions, >> send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or >> visit >> http://www.marist.edu/htbin/wlvindex?LINUX-390 >> -- >> For more information on Linux on System z, visit >> http://wiki.linuxvm.org/ >> > > -- > For LINUX-390 subscribe / signoff / archive access instructions, > send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit > http://www.marist.edu/htbin/wlvindex?LINUX-390 > -- > For more information on Linux on System z, visit > http://wiki.linuxvm.org/ -- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 -- For more information on Linux on System z, visit http://wiki.linuxvm.org/
Re: Creating root LVM
Michael, When you say 'root directory' I assume you mean / and not /root/. FWIW, the only time we use LVMs is for application data or log files in directories such as /opt/was/, /oradata/logs/ or something like that. We used to use an LVM for /var/ but found we didn't need it. We use about a 12 GB file system for Linux (/). If the users fill up regular Linux directories, the answer is 'Stop doing that', and very rarely do they. Hope this helps. -Mike MacIsaac On Tue, Aug 23, 2016 at 8:18 AM, Michael Weiner wrote: > Good morning all, > > I was having a little debate yesterday and I want to get the experts on > this list opinions. > > What's the best practice when it comes to the root directory? > > Is it acceptable and recommend to create an vgroot and lvroot so it is > expandable? > > Or is it recommended to have the root directory as a regular directory and > not expandable. > > Thank you! > > > Sent from my iPhone > > > Sent from my iPhone > -- > For LINUX-390 subscribe / signoff / archive access instructions, > send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or > visit > http://www.marist.edu/htbin/wlvindex?LINUX-390 > -- > For more information on Linux on System z, visit > http://wiki.linuxvm.org/ > -- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 -- For more information on Linux on System z, visit http://wiki.linuxvm.org/
Re: Creating root LVM
Hi Michael, In our shop we use a normal directory to root, and create a VG for the expandable directories. We usually have VG for /usr and /opt. Our cloning scripts are happy with this setup, and we don't have much headache when we have to link the root mdisk to another machine to diagnostics. Mauro http://mauro.limeiratem.com - registered Linux User: 294521 Scripture is both history, and a love letter from God. 2016-08-23 9:18 GMT-03:00 Michael Weiner : > Good morning all, > > I was having a little debate yesterday and I want to get the experts on > this list opinions. > > What's the best practice when it comes to the root directory? > > Is it acceptable and recommend to create an vgroot and lvroot so it is > expandable? > > Or is it recommended to have the root directory as a regular directory and > not expandable. > > Thank you! > > > Sent from my iPhone > > > Sent from my iPhone > -- > For LINUX-390 subscribe / signoff / archive access instructions, > send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or > visit > http://www.marist.edu/htbin/wlvindex?LINUX-390 > -- > For more information on Linux on System z, visit > http://wiki.linuxvm.org/ > -- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 -- For more information on Linux on System z, visit http://wiki.linuxvm.org/
Creating root LVM
Good morning all, I was having a little debate yesterday and I want to get the experts on this list opinions. What's the best practice when it comes to the root directory? Is it acceptable and recommend to create an vgroot and lvroot so it is expandable? Or is it recommended to have the root directory as a regular directory and not expandable. Thank you! Sent from my iPhone Sent from my iPhone -- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 -- For more information on Linux on System z, visit http://wiki.linuxvm.org/
