Re: [systemd-devel] arch linux container filesystems
On Mon, 16.06.14 17:37, Robin Becker (ro...@reportlab.com) wrote: On 16/06/2014 14:00, Dave Reisner wrote: On Mon, Jun 16, 2014 at 01:01:31PM +0100, Robin Becker wrote: Why do I have all the file system duplicates? You don't -- df doesn't understand namespaces. You should use a tool which reads from /proc/self/mountinfo instead of /etc/mtab, e.g. findmnt. If you want df-like output from findmnt, use 'findmnt -vD'. OK thanks; pity we have to abandon old tools and learn a lot of red hat stuff. Price of progress I guess. well, findmnt is neither red hat stuff, it's used all over the distributions. And you shouldn't accept that df can't deal with mount points that reference out-of-namespace sources. File a bug against coreutils, they really should make sure they properly handle the Linux mount logic in that area. Lennart -- Lennart Poettering, Red Hat ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] arch linux container filesystems
On Mon, 16.06.14 13:01, Robin Becker (ro...@reportlab.com) wrote: I asked about this at the arch linux forum, but got no response. I run an up to date arch linux X64 system with systemd-213-9. I built a simple container using the wiki article https://wiki.archlinux.org/index.php/Systemd-nspawn after systemd-nspawn -bD ~/MyContainer and root login I see this in my df output root@MyContainer ~]# df df: '/run/user/1000': No such file or directory df: '/run/user/1000/gvfs': No such file or directory df: '/proc/kmsg (deleted)': No such file or directory df: '/proc/sys/kernel/random/boot_id (deleted)': No such file or directory Filesystem 1K-blocks Used Available Use% Mounted on /dev/sda1 147418744 85779872 54127364 62% / dev 14139004 1413896 1% /dev tmpfs14139000 1413900 0% /dev/shm tmpfs14139000 1413900 0% /sys/fs/cgroup run 1413900 44 1413856 1% /run tmpfs14139000 1413900 0% /tmp tmpfs14139004 1413896 1% /dev tmpfs14139000 1413900 0% /dev/shm tmpfs1413900 44 1413856 1% /run tmpfs14139000 1413900 0% /sys/fs/cgroup tmpfs14139000 1413900 0% /tmp tmpfs 2827840282784 0% /run/user/0 [root@MyContainer ~]# Is this what is expected? Not sure why my user id (1000) is being used. Every user who logs in will nowadays get his own little /run/user/$UID tmpfs directory for runtime purposes, with a strict size limit. logind manages. Since this is a mount df will show it. I can imagine containers might not have /proc/kmsg /proc/sys/kernel/random/boot_id; is that an error in df? These files oiginate in out-of-namespace files the container itself can't see. coreutils should probably get fixed to handle this more gracefully (see other mail). Why do I have all the file system duplicates? Probably because /proc/mounts is a bit limited, and df should probably be smarter and look at /proc/self/mountinfo instead (see other mail). Lennart -- Lennart Poettering, Red Hat ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] arch linux container filesystems
On 20/06/2014 12:48, Lennart Poettering wrote: well, findmnt is neither red hat stuff, it's used all over the distributions. And you shouldn't accept that df can't deal with mount points that reference out-of-namespace sources. File a bug against coreutils, they really should make sure they properly handle the Linux mount logic in that area. Lennart as a matter of fact, my manual page for findmnt lists Karel Zak k...@redhat.com as the sole author if findmnt; that others have adopted it doesn't make it not redhat stuff. You are probably right that this should be fixed in df and (presumably all the other tools that don't work properly in systemd-nspawn containers), but as a general principle I believe if you break it, you own it applies here. As a novice user of these containers, I suspect this kind of error must have been seen before by the systemd developers, so someone among the systemd contributors probably has prior discovery rights to this bug as well. In any case, some might argue that a container (lightweight or not) should be virtually indistinguishable from the original system which would mean such a bug could not happen. -- Robin Becker ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] arch linux container filesystems
On Fri, 20.06.14 15:47, Robin Becker (ro...@reportlab.com) wrote: On 20/06/2014 12:48, Lennart Poettering wrote: well, findmnt is neither red hat stuff, it's used all over the distributions. And you shouldn't accept that df can't deal with mount points that reference out-of-namespace sources. File a bug against coreutils, they really should make sure they properly handle the Linux mount logic in that area. Lennart as a matter of fact, my manual page for findmnt lists Karel Zak k...@redhat.com as the sole author if findmnt; that others have adopted it doesn't make it not redhat stuff. You are probably right that this should be fixed in df and (presumably all the other tools that don't work properly in systemd-nspawn containers), but as a general principle I believe if you break it, you own it applies here. As a novice user of these containers, I suspect this kind of error must have been seen before by the systemd developers, so someone among the systemd contributors probably has prior discovery rights to this bug as well. mount namespaces and bind mounts are in no way a systemd invention. We didn't come up with this, we are not the first users. That's a kernel feature, and since a long time. You might not have noticed this before nspawn, but that's just bad luck, it could have been any other software that uses mount namespaces, like LXC, docker, ... This is in no way a systemd issue, but a general Linux issue. In any case, some might argue that a container (lightweight or not) should be virtually indistinguishable from the original system which would mean such a bug could not happen. Well, these are containers not VMs. They are actually massively different from the host. For example /sys nor /dev are virtualized, and they are unlikely to ever be. Neither is SELinux or anythign like that. Containers *are* distuingishable from normal hosts, and that's by design. And in no way systemd's design but Linux kernel stuff. You are barking up the wrong tree, we didn't introduce these concepts, you just happened to run into them for the first time playing around with systemd, but that's just bad luck. Lennart -- Lennart Poettering, Red Hat ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
[systemd-devel] arch linux container filesystems
I asked about this at the arch linux forum, but got no response. I run an up to date arch linux X64 system with systemd-213-9. I built a simple container using the wiki article https://wiki.archlinux.org/index.php/Systemd-nspawn after systemd-nspawn -bD ~/MyContainer and root login I see this in my df output root@MyContainer ~]# df df: '/run/user/1000': No such file or directory df: '/run/user/1000/gvfs': No such file or directory df: '/proc/kmsg (deleted)': No such file or directory df: '/proc/sys/kernel/random/boot_id (deleted)': No such file or directory Filesystem 1K-blocks Used Available Use% Mounted on /dev/sda1 147418744 85779872 54127364 62% / dev 14139004 1413896 1% /dev tmpfs14139000 1413900 0% /dev/shm tmpfs14139000 1413900 0% /sys/fs/cgroup run 1413900 44 1413856 1% /run tmpfs14139000 1413900 0% /tmp tmpfs14139004 1413896 1% /dev tmpfs14139000 1413900 0% /dev/shm tmpfs1413900 44 1413856 1% /run tmpfs14139000 1413900 0% /sys/fs/cgroup tmpfs14139000 1413900 0% /tmp tmpfs 2827840282784 0% /run/user/0 [root@MyContainer ~]# Is this what is expected? Not sure why my user id (1000) is being used. I can imagine containers might not have /proc/kmsg /proc/sys/kernel/random/boot_id; is that an error in df? Why do I have all the file system duplicates? -- Robin Becker ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] arch linux container filesystems
On Mon, Jun 16, 2014 at 01:01:31PM +0100, Robin Becker wrote: I asked about this at the arch linux forum, but got no response. I run an up to date arch linux X64 system with systemd-213-9. I built a simple container using the wiki article https://wiki.archlinux.org/index.php/Systemd-nspawn after systemd-nspawn -bD ~/MyContainer and root login I see this in my df output root@MyContainer ~]# df df: '/run/user/1000': No such file or directory df: '/run/user/1000/gvfs': No such file or directory df: '/proc/kmsg (deleted)': No such file or directory df: '/proc/sys/kernel/random/boot_id (deleted)': No such file or directory Filesystem 1K-blocks Used Available Use% Mounted on /dev/sda1 147418744 85779872 54127364 62% / dev 14139004 1413896 1% /dev tmpfs14139000 1413900 0% /dev/shm tmpfs14139000 1413900 0% /sys/fs/cgroup run 1413900 44 1413856 1% /run tmpfs14139000 1413900 0% /tmp tmpfs14139004 1413896 1% /dev tmpfs14139000 1413900 0% /dev/shm tmpfs1413900 44 1413856 1% /run tmpfs14139000 1413900 0% /sys/fs/cgroup tmpfs14139000 1413900 0% /tmp tmpfs 2827840282784 0% /run/user/0 [root@MyContainer ~]# Is this what is expected? Not sure why my user id (1000) is being used. I can imagine containers might not have /proc/kmsg /proc/sys/kernel/random/boot_id; is that an error in df? Why do I have all the file system duplicates? You don't -- df doesn't understand namespaces. You should use a tool which reads from /proc/self/mountinfo instead of /etc/mtab, e.g. findmnt. If you want df-like output from findmnt, use 'findmnt -vD'. ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] arch linux container filesystems
On 16/06/2014 14:00, Dave Reisner wrote: On Mon, Jun 16, 2014 at 01:01:31PM +0100, Robin Becker wrote: Why do I have all the file system duplicates? You don't -- df doesn't understand namespaces. You should use a tool which reads from /proc/self/mountinfo instead of /etc/mtab, e.g. findmnt. If you want df-like output from findmnt, use 'findmnt -vD'. OK thanks; pity we have to abandon old tools and learn a lot of red hat stuff. Price of progress I guess. -- Robin Becker ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
