| .. _reportingbugs: |
| |
| .. toctree:: |
| |
| Reporting Bugs |
| ============== |
| |
| Although every situation is different, this page describes how to |
| collect data which will help make efficient use of everyone's time |
| when dealing with vpp bugs. |
| |
| Before you press the Jira button to create a bug report - or email |
| vpp-dev@lists.fd.io - please ask yourself whether there's enough |
| information for someone else to understand and possibly to reproduce |
| the issue given a reasonable amount of effort. **Unicast emails to |
| maintainers, committers, and the project PTL are strongly discouraged.** |
| |
| A good strategy for clear-cut bugs: file a detailed Jira ticket, and |
| then send a short description of the issue to vpp-dev@lists.fd.io, |
| perhaps from the Jira ticket description. It's fine to send email to |
| vpp-dev@lists.fd.io to ask a few questions **before** filing Jira tickets. |
| |
| Data to include in bug reports |
| ============================== |
| |
| Image version and operating environment |
| --------------------------------------- |
| |
| Please make sure to include the vpp image version and command-line arguments. |
| |
| .. code-block:: console |
| |
| $ sudo bash |
| # vppctl show version verbose cmdline |
| Version: v18.07-rc0~509-gb9124828 |
| Compiled by: vppuser |
| Compile host: vppbuild |
| Compile date: Fri Jul 13 09:05:37 EDT 2018 |
| Compile location: /scratch/vpp-showversion |
| Compiler: GCC 7.3.0 |
| Current PID: 5211 |
| Command line arguments: |
| /scratch/vpp-showversion/build-root/install-vpp_debug-native/vpp/bin/vpp |
| unix |
| interactive |
| |
| With respect to the operating environment: if misbehavior involving a |
| specific VM / container / bare-metal environment is involved, please |
| describe the environment in detail: |
| |
| * Linux Distro (e.g. Ubuntu 14.04.3 LTS, CentOS-7, etc.) |
| * NIC type(s) (ixgbe, i40e, enic, etc. etc.), vhost-user, tuntap |
| * NUMA configuration if applicable |
| |
| Please note the CPU architecture (x86_86, aarch64), and hardware platform. |
| |
| When practicable, please report issues against released software, or |
| unmodified master/latest software. |
| |
| "Show" command output |
| --------------------- |
| |
| Every situation is different. If the issue involves a sequence of debug CLI command, please enable CLI command logging, and send the sequence involved. Note that the debug CLI is a developer's tool - **no warranty express or implied** - and that we may choose not to fix debug CLI bugs. |
| |
| Please include "show error" [error counter] output. It's often helpful to "clear error", send a bit of traffic, then "show error" particularly when running vpp on a noisy networks. |
| |
| Please include ip4 / ip6 / mpls FIB contents ("show ip fib", "show ip6 fib", "show mpls fib", "show mpls tunnel"). |
| |
| Please include "show hardware", "show interface", and "show interface address" output |
| |
| Here is a consolidated set of commands that are generally useful before/after sending traffic. Before sending traffic. |
| |
| .. code-block:: console |
| |
| vppctl clear hardware |
| vppctl clear interface |
| vppctl clear error |
| vppctl clear run |
| |
| Send some traffic and then issue the following commands. |
| |
| .. code-block:: console |
| |
| vppctl show version verbose |
| vppctl show hardware |
| vppctl show hardware address |
| vppctl show interface |
| vppctl show run |
| vppctl show error |
| |
| Here are some protocol specific show commands that may also make |
| sense. Only include those features which have been configured. |
| |
| .. code-block:: console |
| |
| vppctl show l2fib |
| vppctl show bridge-domain |
| |
| vppctl show ip fib |
| vppctl show ip arp |
| |
| vppctl show ip6 fib |
| vppctl show ip6 neighbors |
| |
| vppctl show mpls fib |
| vppctl show mpls tunnel |
| |
| Network Topology |
| ---------------- |
| |
| Please include a crisp description of the network topology, including |
| L2 / IP / MPLS / segment-routing addressing details. If you expect |
| folks to reproduce and debug issues, this is a must. |
| |
| At or above a certain level of topological complexity, it becomes |
| problematic to reproduce the original setup. |
| |
| Packet Tracer Output |
| -------------------- |
| |
| If you capture packet tracer output which seems relevant, please include it. |
| |
| .. code-block:: console |
| |
| vppctl trace add dpdk-input 100 # or similar |
| |
| send-traffic |
| |
| .. code-block:: console |
| |
| vppctl show trace |
| |
| Capturing post-mortem data |
| ========================== |
| |
| It should go without saying, but anyhow: **please put post-mortem data |
| in obvious, accessible places.** Time wasted trying to acquire |
| accounts, credentials, and IP addresses simply delays problem |
| resolution. |
| |
| Please remember to add post-mortem data location information to Jira |
| tickets. |
| |
| Syslog Output |
| ------------- |
| |
| The vpp signal handler typically writes a certain amount of data in |
| /var/log/syslog before exiting. Make sure to check for evidence, e.g |
| via "grep /usr/bin/vpp /var/log/syslog" or similar. |
| |
| Binary API Trace |
| ---------------- |
| |
| If the issue involves a sequence of control-plane API messages - even |
| a very long sequence - please enable control-plane API |
| tracing. Control-plane API post-mortem traces end up in |
| /tmp/api_post_mortem.<pid>. |
| |
| Please remember to put post-mortem binary api traces in accessible |
| places. |
| |
| These API traces are especially helpful in cases where the vpp engine |
| is throwing traffic on the floor, e.g. for want of a default route or |
| similar. |
| |
| Make sure to leave the default stanza "... api-trace { on } ... " in |
| the vpp startup configuration file /etc/vpp/startup.conf, or to |
| include it in the command line arguments passed by orchestration |
| software. |
| |
| Core Files |
| ---------- |
| |
| Production systems, as well as long-running pre-production soak-test |
| systems, **must** arrange to collect core images. There are various |
| ways to configure core image capture, including e.g. the Ubuntu |
| "corekeeper" package. In a pinch, the following very basic sequence |
| will capture usable vpp core files in /tmp/dumps. |
| |
| .. code-block:: console |
| |
| # mkdir -p /tmp/dumps |
| # sysctl -w debug.exception-trace=1 |
| # sysctl -w kernel.core_pattern="/tmp/dumps/%e-%t" |
| # ulimit -c unlimited |
| # echo 2 > /proc/sys/fs/suid_dumpable |
| |
| Vpp core files often appear enormous. Gzip typically compresses them |
| to manageable sizes. A multi-GByte corefile often compresses to 10-20 |
| Mbytes. |
| |
| Please remember to put compressed core files in accessible places. |
| |
| Make sure to leave the default stanza "... unix { ... full-coredump |
| ... } ... " in the vpp startup configuration file |
| /etc/vpp/startup.conf, or to include it in the command line arguments |
| passed by orchestration software. |
| |
| Core files from private, modified images are discouraged. If it's |
| necessary to go that route, please copy the **exact** Debian |
| packages (or RPMs) corresponding to the core file to the same public |
| place as the core file. In particular. |
| |
| * vpp_<version>_<arch>.deb # the vpp executable |
| * vpp-dbg_<version>_<arch>.deb # debug symbols |
| * vpp-dev_<version>_<arch>.deb # development package |
| * vpp-lib_<version>_<arch>.deb # shared libraries |
| * vpp-plugins_<version>_<arch>.deb # plugins |
| |
| Please include the full commit-ID the Jira ticket. |
| |
| If we go through the setup process only to discover that the image and |
| core files don't match, it will simply delay resolution of the |
| issue. And it will annoy the heck out of the engineer who just wasted |
| their time. Exact means **exact**, not "oh, gee, I added a few lines |
| of debug scaffolding since then..." |