similar to: collectd leaks SIGCHLD == SIG_IGN into plugins

On Tue, Nov 13, 2018 at 10:04:33AM +0000, Daniel P. Berrangé wrote: > On Fri, Nov 09, 2018 at 12:19:30PM +0000, Richard W.M. Jones wrote: > > Peter Dimitrov and myself were debugging a very peculiar bug when > > libguestfs is run as a plugin from collectd: > > > > https://www.redhat.com/archives/libguestfs/2018-November/thread.html#00023 > > > > The long

Here are strace outputs per process. strace_output.22076 is the plugin's pid. (A little before forking) strace_output.22077 runs qemu-img strace_output.22078 is a mystery to me strace_output.22079 is rm -rf to the overlay image and its temporary dir. Best Regards, Peter On Wed, Nov 7, 2018 at 4:38 PM Richard W.M. Jones <rjones@redhat.com> wrote: > On Wed, Nov 07, 2018 at

On Fri, Nov 09, 2018 at 12:19:30PM +0000, Richard W.M. Jones wrote: > Peter Dimitrov and myself were debugging a very peculiar bug when > libguestfs is run as a plugin from collectd: > > https://www.redhat.com/archives/libguestfs/2018-November/thread.html#00023 > > The long story short is that collectd leaks SIGCHLD == SIG_IGN setting > into plugins: > >

I was extending the virt plugin. It already collects similar data (about VMs) using Libvirt's API, but lacks disk usage information. I went through some hoops to link libguestfs correctly to collectd. Is it okay to just include fork(), waitpid() example? It does reproduce the issue. Best Regards, Peter On Tue, Nov 13, 2018 at 1:34 PM Richard W.M. Jones <rjones@redhat.com> wrote:

Hi Rich, On Fri, Nov 9, 2018 at 1:19 PM, Richard W.M. Jones <rjones@redhat.com> wrote: > Peter Dimitrov and myself were debugging a very peculiar bug when > libguestfs is run as a plugin from collectd: > > https://www.redhat.com/archives/libguestfs/2018-November/thread.html#00023 > > The long story short is that collectd leaks SIGCHLD == SIG_IGN setting > into

Hi, thank you very much for reporting this! Sounds like a bug in the exec plugin – it never ceases to amaze me how many issues a single plugin can have ;) > > > This means that any plugin that does the usual pattern of: > > > > > > pid = fork (); Note that the exec plugin is the *only* plugin that does this. All other plugins are forbidden to fork(), popen() or

On Tue, Nov 13, 2018 at 03:17:33PM +0200, Peter Dimitrov wrote: > I was extending the virt plugin. > It already collects similar data (about VMs) using Libvirt's API, but lacks > disk usage information. > > I went through some hoops to link libguestfs correctly to collectd. > Is it okay to just include fork(), waitpid() example? It does reproduce the > issue. Yes, I

A quick glance shows that the exec plugin actually is clearing the signal mask: https://github.com/collectd/collectd/blob/master/src/exec.c#L526 Can you give some more context when this problem comes up? Ideally in a Github issue (hint, hint ;). -- Florian octo Forster Hacker in training GnuPG: 0x0C705A15 http://octo.it/

On Tue, Nov 13, 2018 at 12:00:19PM +0100, Florian Forster wrote: > Hi, > > thank you very much for reporting this! Sounds like a bug in the exec plugin – > it never ceases to amaze me how many issues a single plugin can have ;) > > > > > This means that any plugin that does the usual pattern of: > > > > > > > > pid = fork (); > > Note

Thank you, Rich, This was the issue indeed. export LIBGUESTFS_BACKEND=direct fixed it. The next step I tried was to integrate libguestfs in collectd virt plugin to collect this data automatically. In this case I'm having an unknown error in add_libvirt_dom() (same with add_domain) when it's invoking qemu-img to create overlay image. There is no difference between manual and service

On Thu, Nov 08, 2018 at 04:51:31PM +0200, Peter Dimitrov wrote: > Here are strace outputs per process. > > strace_output.22076 is the plugin's pid. (A little before forking) Ah ha. Close reading of the waitpid(2) man page says: ECHILD (for waitpid() or waitid()) The process specified by pid (wait‐ pid()) or idtype and id (waitid()) does not exist or is not

> That makes no sense because we are supposed to have just forked successfully I just realized libguestfs uses fork. Now we know why qemu-img worked - I launched it with popen. > So it must be something to do with collectd and how it runs programs. > Is it using LD_PRELOAD trickery, or replacing libc, or using seccomp? If I understand the question correctly - it's about how

Rsync maintainers please review rsync bug https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=98740 The code in question is in socket.c in start_accept_loop. The user is getting these warning messages:

Hello, I have a simple C program that uses libguestfs to extract info about disk usage from a libvirt domain. It works when ran manually as root, but fails when started as a systemd service. I'm attaching the service file, source code and verbose logs from both the successful manual run and from the service journal. SELinix is disabled. Error messages: libguestfs:

--- scripts/ovirt | 2 +- scripts/ovirt-config-collectd | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/scripts/ovirt b/scripts/ovirt index 8296783..4a7cbc7 100755 --- a/scripts/ovirt +++ b/scripts/ovirt @@ -43,7 +43,7 @@ start() { log "skipping ovirt-awake, oVirt identify service not available" fi - find_srv collectd tcp +

--- .../modules/ovirt/templates/ovirt-dns.conf.erb | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/installer/modules/ovirt/templates/ovirt-dns.conf.erb b/installer/modules/ovirt/templates/ovirt-dns.conf.erb index ae3eb48..f4ee39b 100644 --- a/installer/modules/ovirt/templates/ovirt-dns.conf.erb +++ b/installer/modules/ovirt/templates/ovirt-dns.conf.erb @@ -1,7 +1,7

While nbdkit itself must run with SIGPIPE ignored, many applications expect to inherit SIGPIPE in the default state. What's worse, POSIX states that a non-interactive shell script cannot use 'trap' to undo an inherited SIG_IGN on SIGPIPE. I have seen several bug reports over the years of something that works for a developer but fails under a CI environment, where the root cause was

Some background information. I have used Debian with Asterisk for several years. Have encountered zero problems. I am now trying to setup an Asterisk on a CentOS7 box using VMWare Workstation. I am brand new to CentOS and RHEL so I may be missing something obvious. I am installing CentOS Minimal Install and Asterisk from Source. (I have installed Asterisk from Source on Debian hundreds of

Hi. We sometimes/often get such errors. It occures in main.c/client_run(). I investigated further and found, that the waitpid() in main.c/wait_process() exits with -1, errno = ECHILD, which means "No children". *status can contain garbage in such cases - but not always. It happens under Solaris-2.5.1/SPARC. It (ECHILD) also happens on other Solaris versions - but there *status seems to

Hi! I'm unable to write with remote rsync in daemon mode. ********* My configuration: rsync 2.6.2 Linux 2.4.20-alt16-up (ALTLinux www.altlinux.org) (There is owl-patch in ALTLinux-kernel) ========== /etc/rsyncd.conf ============= log file = /var/log/rsync [routers] comment = Our Backups path = /mnt/backup/routers uid = archiver gid = archiver use chroot = true read only = false list = true