[sflow]: Build infrastructure changes to support sflow docker and utilities (sonic-net#3251)

Introduce a new "sflow" container (if ENABLE_SFLOW is set). The new docker will include:
hsflowd : host-sflow based daemon is the sFlow agent
psample : Built from libpsample repository. Useful in debugging sampled packets/groups.
sflowtool : Locally dump sflow samples (e.g. with a in-unit collector)

In case of SONiC-VS, enable psample & act_sample kernel modules.

VS' syncd needs iproute2=4.20.0-2~bpo9+1 & libcap2-bin=1:2.25-1 to support tc-sample

tc-syncd is provided as a convenience tool for debugging (e.g. tc-syncd filter show ...)

Author: padmanarayana

dockers/docker-sflow/Dockerfile.j2

@@ -0,0 +1,33 @@
+{% from "dockers/dockerfile-macros.j2" import install_debian_packages, install_python_wheels, copy_files %}
+FROM docker-config-engine-stretch
+
+ARG docker_container_name
+RUN [ -f /etc/rsyslog.conf ] && sed -ri "s/%syslogtag%/$docker_container_name#%syslogtag%/;" /etc/rsyslog.conf
+
+## Make apt-get non-interactive
+ENV DEBIAN_FRONTEND=noninteractive
+
+RUN apt-get update      && \
+    apt-get install -f -y  \
+            dmidecode      \
+            libmnl0=1.0.4-2
+
+{% if docker_sflow_debs.strip() -%}
+# Copy locally-built Debian package dependencies
+{{ copy_files("debs/", docker_sflow_debs.split(' '), "/debs/") }}
+
+# Install locally-built Debian packages and implicitly install their dependencies
+{{ install_debian_packages(docker_sflow_debs.split(' ')) }}
+{%- endif %}
+
+RUN apt-get clean -y      && \
+    apt-get autoclean -y  && \
+    apt-get autoremove -y && \
+    rm -rf /debs
+
+RUN sed -ri '/^DAEMON_ARGS=""/c DAEMON_ARGS="-c /var/log/hsflowd.crash"' /etc/init.d/hsflowd
+
+COPY ["start.sh", "/usr/bin/"]
+COPY ["supervisord.conf", "/etc/supervisor/conf.d/"]
+
+ENTRYPOINT ["/usr/bin/supervisord"]

dockers/docker-sflow/base_image_files/psample

@@ -0,0 +1,10 @@
+#!/bin/bash
+
+DOCKER_EXEC_FLAGS="i"
+
+# Determine whether stdout is on a terminal
+if [ -t 1 ] ; then
+    DOCKER_EXEC_FLAGS+="t"
+fi
+
+docker exec -$DOCKER_EXEC_FLAGS sflow psample "$@"

dockers/docker-sflow/base_image_files/sflowtool

@@ -0,0 +1,10 @@
+#!/bin/bash
+
+DOCKER_EXEC_FLAGS="i"
+
+# Determine whether stdout is on a terminal
+if [ -t 1 ] ; then
+    DOCKER_EXEC_FLAGS+="t"
+fi
+
+docker exec -$DOCKER_EXEC_FLAGS sflow sflowtool "$@"

dockers/docker-sflow/start.sh

@@ -0,0 +1,7 @@
+#!/usr/bin/env bash
+
+rm -f /var/run/rsyslogd.pid
+
+supervisorctl start rsyslogd
+
+supervisorctl start sflowmgrd

dockers/docker-sflow/supervisord.conf

@@ -0,0 +1,28 @@
+[supervisord]
+logfile_maxbytes=1MB
+logfile_backups=2
+nodaemon=true
+
+[program:start.sh]
+command=/usr/bin/start.sh
+priority=1
+autostart=true
+autorestart=false
+stdout_logfile=syslog
+stderr_logfile=syslog
+
+[program:rsyslogd]
+command=/usr/sbin/rsyslogd -n
+priority=2
+autostart=false
+autorestart=false
+stdout_logfile=syslog
+stderr_logfile=syslog
+
+[program:sflowmgrd]
+command=/usr/bin/sflowmgrd
+priority=3
+autostart=false
+autorestart=false
+stdout_logfile=syslog
+stderr_logfile=syslog

files/build_templates/sflow.service.j2

@@ -0,0 +1,14 @@
+[Unit]
+Description=sFlow container
+Requires=swss.service
+After=swss.service
+Before=ntp-config.service
+
+[Service]
+User={{ sonicadmin_user }}
+ExecStartPre=/usr/bin/{{docker_container_name}}.sh start
+ExecStart=/usr/bin/{{docker_container_name}}.sh wait
+ExecStop=/usr/bin/{{docker_container_name}}.sh stop
+
+[Install]
+WantedBy=multi-user.target

files/build_templates/sonic_debian_extension.j2

@@ -300,6 +300,14 @@ sudo cp $IMAGE_CONFIGS/platform/rc.local $FILESYSTEM_ROOT/etc/
 ## copy blacklist file
 sudo cp $IMAGE_CONFIGS/platform/linux_kernel_bde.conf $FILESYSTEM_ROOT/etc/modprobe.d/
 
+# Enable psample drivers to support sFlow on vs
+{% if sonic_asic_platform == "vs" %}
+sudo tee -a $FILESYSTEM_ROOT/etc/modules-load.d/modules.conf > /dev/null <<EOF
+psample
+act_sample
+EOF
+{% endif %}
+
 ## Bind docker path
 if [[ $CONFIGURED_ARCH == armhf || $CONFIGURED_ARCH == arm64 ]]; then
     sudo mkdir -p $FILESYSTEM_ROOT/dockerfs

platform/vs/docker-syncd-vs/Dockerfile.j2

@@ -8,6 +8,8 @@ ENV DEBIAN_FRONTEND=noninteractive
 
 RUN apt-get update
 
+RUN apt-get install -f -y iproute2=4.20.0-2~bpo9+1 libcap2-bin=1:2.25-1
+
 COPY \
 {% for deb in docker_syncd_vs_debs.split(' ') -%}
 debs/{{ deb }}{{' '}}

rules/config

@@ -95,3 +95,6 @@ FRR_USER_GID = 300
 
 # Default VS build memory preparation
 DEFAULT_VS_PREPARE_MEM = yes
+
+# ENABLE_SYSTEM_SFLOW - build docker-sonic-sflow for sFlow support
+ENABLE_SFLOW = y

rules/docker-sflow.mk

@@ -0,0 +1,35 @@
+# docker image for sFlow agent
+
+DOCKER_SFLOW_STEM = docker-sflow
+DOCKER_SFLOW = $(DOCKER_SFLOW_STEM).gz
+DOCKER_SFLOW_DBG = $(DOCKER_SFLOW_STEM)-$(DBG_IMAGE_MARK).gz
+
+$(DOCKER_SFLOW)_PATH = $(DOCKERS_PATH)/$(DOCKER_SFLOW_STEM)
+
+$(DOCKER_SFLOW)_DEPENDS += $(SWSS) $(REDIS_TOOLS) $(HSFLOWD) $(SFLOWTOOL) $(PSAMPLE)
+$(DOCKER_SFLOW)_DBG_DEPENDS = $($(DOCKER_CONFIG_ENGINE_STRETCH)_DBG_DEPENDS)
+$(DOCKER_TEAMD)_DBG_DEPENDS += $(SWSS_DBG) $(LIBSWSSCOMMON_DBG)
+$(DOCKER_SFLOW)_DBG_IMAGE_PACKAGES = $($(DOCKER_CONFIG_ENGINE_STRETCH)_DBG_IMAGE_PACKAGES)
+
+$(DOCKER_SFLOW)_LOAD_DOCKERS += $(DOCKER_CONFIG_ENGINE_STRETCH)
+
+SONIC_DOCKER_IMAGES += $(DOCKER_SFLOW)
+ifeq ($(ENABLE_SFLOW), y)
+SONIC_INSTALL_DOCKER_IMAGES += $(DOCKER_SFLOW)
+SONIC_STRETCH_DOCKERS += $(DOCKER_SFLOW)
+endif
+
+SONIC_DOCKER_DBG_IMAGES += $(DOCKER_SFLOW_DBG)
+ifeq ($(ENABLE_SFLOW), y)
+SONIC_INSTALL_DOCKER_DBG_IMAGES += $(DOCKER_SFLOW_DBG)
+SONIC_STRETCH_DBG_DOCKERS += $(DOCKER_SFLOW_DBG)
+endif
+
+$(DOCKER_SFLOW)_CONTAINER_NAME = sflow
+$(DOCKER_SFLOW)_RUN_OPT += --net=host --privileged -t
+$(DOCKER_SFLOW)_RUN_OPT += -v /etc/sonic:/etc/sonic:ro
+$(DOCKER_SFLOW)_RUN_OPT += -v /host/warmboot:/var/warmboot
+
+$(DOCKER_SFLOW)_BASE_IMAGE_FILES += psample:/usr/bin/psample
+$(DOCKER_SFLOW)_BASE_IMAGE_FILES += sflowtool:/usr/bin/sflowtool
+