Description of problem: Mobile broadband connection intermittently fails to establish in Fedora 26 (upgraded from 25). Strangely it *sometimes* worked. The connection worked as expected in previous F25. Version-Release number of selected component (if applicable): F26, particularly when upgraded from F25? How reproducible: 80% of the time (subjectively) Steps to Reproduce: 1. Upgrade to F26 (e.g. from 25) 2. Connect (or create and connect) a mobile broadband connection via Network Manager 3. Attempt to connect Actual results: - The Gnome Network Manager UI returns to a non-connected state. - mcli conn up uuid ..... shows "PPP service failed to start" - journalct (system log) gives more info: ttyUSB0): error starting PPP: the PPP plugin /usr/lib64/NetworkManager/libnm-ppp-plugin.so is not installed Expected results: A connection to be established Additional info: Installing "NetworkManager-ppp" resolves the problem. I'm unsure if this is a new package for Network Manager 1.8? ; however it wasn't installed during the upgrade.
Hi, I install "NetworkManager-ppp" package and it did work. Ref: https://bugzilla.redhat.com/show_bug.cgi?id=1385198. Regards, Thilina.
This seems to be a bug in DNF or the solver. Here's a log from the system with f25 versions of lz4 and NetworkManager of dnf doing the wrong thing on update (with commentary): 0.) Attempt a NetworkManager update. This is wrong -- the NetworkManager-ppp obsoletes the old NetworkManager package and should be in the transaction: [root@belphegor ~]# dnf --debugsolver update NetworkManager Last metadata expiration check: 0:15:29 ago on Thu Jul 20 20:36:26 2017. Dependencies resolved. ================================================================================ Package Arch Version Repository Size ================================================================================ Upgrading: NetworkManager x86_64 1:1.8.0-6.fc26 fedora 1.6 M NetworkManager-libnm x86_64 1:1.8.0-6.fc26 fedora 1.2 M Transaction Summary ================================================================================ Upgrade 2 Packages Total download size: 2.8 M Is this ok [y/N]: Operation aborted. [root@belphegor ~]# mv debugdata debugdata0 1.) See what other updates are pending (the filesystem update is probably unrelated): [root@belphegor ~]# dnf --debugsolver update Last metadata expiration check: 0:16:03 ago on Thu Jul 20 20:36:26 2017. Dependencies resolved. ================================================================================ Package Arch Version Repository Size ================================================================================ Upgrading: NetworkManager x86_64 1:1.8.0-6.fc26 fedora 1.6 M NetworkManager-libnm x86_64 1:1.8.0-6.fc26 fedora 1.2 M filesystem x86_64 3.2-40.fc26 fedora 1.1 M lz4 x86_64 1.7.5-4.fc26 updates 90 k Installing dependencies: lz4-libs x86_64 1.7.5-4.fc26 updates 47 k replacing lz4.x86_64 1.7.5-1.fc25 Transaction Summary ================================================================================ Install 1 Package Upgrade 4 Packages Total download size: 4.0 M Is this ok [y/N]: Operation aborted. [root@belphegor ~]# mv debugdata debugdata1 2.) Cool, let's do the lz4 update: [root@belphegor ~]# dnf --debugsolver -y update lz4 Last metadata expiration check: 0:16:26 ago on Thu Jul 20 20:36:26 2017. Dependencies resolved. ================================================================================ Package Arch Version Repository Size ================================================================================ Upgrading: lz4 x86_64 1.7.5-4.fc26 updates 90 k Installing dependencies: lz4-libs x86_64 1.7.5-4.fc26 updates 47 k replacing lz4.x86_64 1.7.5-1.fc25 Transaction Summary ================================================================================ Install 1 Package Upgrade 1 Package Total download size: 137 k Downloading Packages: (1/2): lz4-libs-1.7.5-4.fc26.x86_64.rpm 6.8 MB/s | 47 kB 00:00 (2/2): lz4-1.7.5-4.fc26.x86_64.rpm 11 MB/s | 90 kB 00:00 -------------------------------------------------------------------------------- Total 123 kB/s | 137 kB 00:01 Running transaction check Transaction check succeeded. Running transaction test Transaction test succeeded. Running transaction Preparing : 1/1 Upgrading : lz4-1.7.5-4.fc26.x86_64 1/3 Installing : lz4-libs-1.7.5-4.fc26.x86_64 2/3 Running scriptlet: lz4-libs-1.7.5-4.fc26.x86_64 2/3 Cleanup : lz4-1.7.5-1.fc25.x86_64 3/3 Running scriptlet: lz4-1.7.5-1.fc25.x86_64 3/3 Verifying : lz4-libs-1.7.5-4.fc26.x86_64 1/3 Verifying : lz4-1.7.5-4.fc26.x86_64 2/3 Verifying : lz4-1.7.5-1.fc25.x86_64 3/3 Installed: lz4-libs.x86_64 1.7.5-4.fc26 Upgraded: lz4.x86_64 1.7.5-4.fc26 Complete! [root@belphegor ~]# mv debugdata debugdata2 3.) Wtf! The lz4 update seemingly changed dnf's mind about the NetworkManager obsolete and now it works all right: [root@belphegor ~]# dnf --debugsolver update Last metadata expiration check: 0:16:46 ago on Thu Jul 20 20:36:26 2017. Dependencies resolved. ================================================================================ Package Arch Version Repository Size ================================================================================ Upgrading: NetworkManager x86_64 1:1.8.0-6.fc26 fedora 1.6 M NetworkManager-libnm x86_64 1:1.8.0-6.fc26 fedora 1.2 M filesystem x86_64 3.2-40.fc26 fedora 1.1 M Installing dependencies: NetworkManager-ppp x86_64 1:1.8.0-6.fc26 fedora 127 k replacing NetworkManager.x86_64 1:1.4.4-5.fc25 Transaction Summary ================================================================================ Install 1 Package Upgrade 3 Packages Total download size: 4.0 M Is this ok [y/N]: Operation aborted. [root@belphegor ~]# mv debugdata debugdata3
Created attachment 1302009 [details] Debug traces from the solver
0) Totally agree. I think this is connected tight with multiple obsoletes for NM + Provides: NM in NM-ppp 1+3) This really feels like some bug in libsolv in yumobs.... Michael, could you please take a look?
There is a bogus queue_empty() line in the yumobs code, so that it can only deal with one obsoletes. That's why it works after the lz4 update. Fixed with libsolv commit fe64933a5c9125401f0ae3e928c406d19075c202 As said in the commit message, It's surprising that nobody ran into this bug until now.
libsolv-0.6.28-2.fc26 has been submitted as an update to Fedora 26. https://bodhi.fedoraproject.org/updates/FEDORA-2017-6a351d5cc9
(In reply to Michael Schröder from comment #5) > There is a bogus queue_empty() line in the yumobs code, so that it can only > deal with one obsoletes. That's why it works after the lz4 update. > > Fixed with libsolv commit fe64933a5c9125401f0ae3e928c406d19075c202 > > As said in the commit message, It's surprising that nobody ran into this bug > until now. Thanks a lot for investigating and fixing issue!
libsolv-0.6.28-2.fc25 has been pushed to the Fedora 25 testing repository. If problems still persist, please make note of it in this bug report. See https://fedoraproject.org/wiki/QA:Updates_Testing for instructions on how to install test updates. You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2017-c466a496c1
libsolv-0.6.28-2.fc26 has been pushed to the Fedora 26 testing repository. If problems still persist, please make note of it in this bug report. See https://fedoraproject.org/wiki/QA:Updates_Testing for instructions on how to install test updates. You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2017-6a351d5cc9
libsolv-0.6.28-2.fc26 has been pushed to the Fedora 26 stable repository. If problems still persist, please make note of it in this bug report.
libsolv-0.6.28-2.fc25 has been pushed to the Fedora 25 stable repository. If problems still persist, please make note of it in this bug report.
LGTM. Thanks for investigating and fixing promptly.