- Why I did it
The pcie configuration file location is under plugin directory not under platform directory.
#6437
- How I did it
Move all pcie.yaml configuration file from plugin to platform directory.
Remove unnecessary timer to start pcie-check.service
Move pcie-check.service to sonic-host-services
- How to verify it
Verify on the device
- Why I did it
Group all SONiC services together and able to manage them together. Will be used in config reload command as much simpler and generic way to restart services.
- How I did it
Add services to sonic.target
- How to verify it
Together with Azure/sonic-utilities#1199
config reload -y
Signed-off-by: Stepan Blyshchak <stepanb@nvidia.com>
Fix marvell-armhf build break
The azure-storage package depends on the cryptography package. Newer
versions of cryptography require the rust compiler, the correct version
for which is not readily available in buster. Hence we pre-install an
older version here to satisfy the azure-storage dependency.
Note: This is not a problem for other architectures as pre-built versions
of cryptography are available for those. This sequence can be removed
after upgrading to debian bullseye.
- Make PDDF code compliant with both Python 2 and Python 3
- Align code with PEP8 standards using autopep8
- Build and install both Python 2 and Python 3 PDDF packages
**- Why I did it**
This PR aims to monitor the running status of each container. Currently the auto-restart feature was enabled. If a critical process exited unexpected, the container will be restarted. If the container was restarted 3 times during 20 minutes, then it will not run anymore unless we cleared the flag using the command `sudo systemctl reset-failed <container_name>` manually.
**- How I did it**
We will employ Monit to monitor a script. This script will generate the expected running container list and compare it with the current running containers. If there are containers which were expected to run but were not running, then an alerting message will be written into syslog.
**- How to verify it**
I tested this feature on a lab device `str-a7050-acs-3` which has single ASIC and `str2-n3164-acs-3` which has a Multi-ASIC. First I manually stopped a container by running the command `sudo systemctl stop <container_name>`, then I checked whether there was an alerting message in the syslog.
Signed-off-by: Yong Zhao <yozhao@microsoft.com>
* First cut image update for kubernetes support.
With this,
1) dockers dhcp_relay, lldp, pmon, radv, snmp, telemetry are enabled
for kube management
init_cfg.json configure set_owner as kube for these
2) Each docker's start.sh updated to call container_startup.py to register going up
As part of this call, it registers the current owner as local/kube and its version
The images are built with its version ingrained into image during build
3) Update all docker's bash script to call 'container start/stop/wait' instead of 'docker start/stop/wait'.
For all locally managed containers, it calls docker commands, hence no change for locally managed.
4) Introduced a new ctrmgrd service, that helps with transition between owners as kube & local and carry over any labels update from STATE-DB to API server
5) hostcfgd updated to handle owner change
6) Reboot scripts are updatd to tag kube running images as local, so upon reboot they run the same image.
7) Added kube_commands.py to handle all updates with Kubernetes API serrver -- dedicated for k8s interaction only.
Added source interface support for NTP.
Also made NTP start on Mgmt-VRF by default when configured.
**- How I did it**
1) Updated hostcfg to listen to global config NTP and NTP_SERVER tables and restart ntp when ever the configuration changes. NTP table includes source interface configuration.
2) The ntp script updated to by default start on Mgmt-VFT when configured.
Signed-off-by: Prabhu Sreenivasan <prabhu.sreenivasan@broadcom>
Install the 'wheel' package in host OS (along with python3 and python3-distutils which are also needed for building some Python packages) to eliminate error messages like the following:
```
Running setup.py bdist_wheel for watchdog: started
Running setup.py bdist_wheel for watchdog: finished with status 'error'
Complete output from command /usr/bin/python -u -c "import setuptools, tokenize;__file__='/tmp/pip-install-Qd3K08/watchdog/setup.py';f=getattr(tokenize, 'open', open)(__file__);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))" bdist_wheel -d /tmp/pip-wheel-0AHpMe --python-tag cp27:
usage: -c [global_opts] cmd1 [cmd1_opts] [cmd2 [cmd2_opts] ...]
or: -c --help [cmd1 cmd2 ...]
or: -c --help-commands
or: -c cmd --help
error: invalid command 'bdist_wheel'
----------------------------------------
Failed building wheel for watchdog
```
These error messages appear to have no impact on the image build, because the Python package seems to still get installed successfully afterward, just the building of a wheel package fails. Therefore, this is more of a cosmetic fix than an actual bug.
This is an addendum to https://github.com/Azure/sonic-buildimage/pull/6182.
Also upgrade pip and install more recent version of setuptools package via PyPI.
libxslt-dev and libz-dev are dependencies for lxml==4.6.1 which is required for pyangbind==0.8.1
lxml-4.6.2-cp37-cp37m-manylinux1_x86_64.whl is directly downloaded in amd64 whereas in arm this is built from lxml-4.6.2.tar.gz
Signed-off-by: Sabareesh Kumar Anandan <sanandan@marvell.com>
**- Why I did it**
To support dynamic buffer calculation.
This PR also depends on the following PRs for sub modules
- [sonic-swss: [buffermgr/bufferorch] Support dynamic buffer calculation #1338](https://github.com/Azure/sonic-swss/pull/1338)
- [sonic-swss-common: Dynamic buffer calculation #361](https://github.com/Azure/sonic-swss-common/pull/361)
- [sonic-utilities: Support dynamic buffer calculation #973](https://github.com/Azure/sonic-utilities/pull/973)
**- How I did it**
1. Introduce field `buffer_model` in `DEVICE_METADATA|localhost` to represent which buffer model is running in the system currently:
- `dynamic` for the dynamic buffer calculation model
- `traditional` for the traditional model in which the `pg_profile_lookup.ini` is used
2. Add the tables required for the feature:
- ASIC_TABLE in platform/\<vendor\>/asic_table.j2
- PERIPHERAL_TABLE in platform/\<vendor\>/peripheral_table.j2
- PORT_PERIPHERAL_TABLE on a per-platform basis in device/\<vendor\>/\<platform\>/port_peripheral_config.j2 for each platform with gearbox installed.
- DEFAULT_LOSSLESS_BUFFER_PARAMETER and LOSSLESS_TRAFFIC_PATTERN in files/build_templates/buffers_config.j2
- Add lossless PGs (3-4) for each port in files/build_templates/buffers_config.j2
3. Copy the newly introduced j2 files into the image and rendering them when the system starts
4. Update the CLI options for buffermgrd so that it can start with dynamic mode
5. Fetches the ASIC vendor name in orchagent:
- fetch the vendor name when creates the docker and pass it as a docker environment variable
- `buffermgrd` can use this passed-in variable
6. Clear buffer related tables from STATE_DB when swss docker starts
7. Update the src/sonic-config-engine/tests/sample_output/buffers-dell6100.json according to the buffer_config.j2
8. Remove buffer pool sizes for ingress pools and egress_lossy_pool
Update the buffer settings for dynamic buffer calculation
python2 is end of life and SONiC is going to support python3. This PR is going to support:
1. Mellanox SONiC platform API python3 support
2. Install both python2 and python3 verson of Mellanox SONiC platform API or pmon and host side
ntp-systemd-wrapper file from files/image_config/ntp was not getting picked up. Added a line on sonic_debian_extension.j2 to copy over the file from files/image_config/ntp after installing the debian package.
Signed-off-by: Prabhu Sreenivasan <prabhu.sreenivasan@broadcom.com>
- Allow platform specific reboot script to be called after crash kernel has
finished copying the kernel vmcore
- Disable pcie advanced features when running crash kernel. This improves
reliability of the crash kernel to successfully create a vmcore and also
reboot
- Allow crash kernel to reboot if a panic is seen while it is generating a
vmcore
- Fix crash kernel to use the SONiC specific /usr/local/bin/reboot script
instead of the Linux reboot command /sbin/reboot
- Use sonic_platform as the kernel command line parameter to pass platform identifier string
Signed-off-by: Rajendra Dendukuri <rajendra.dendukuri@broadcom.com>
Barefoot platform vendors' sonic_platform packages import the Python 'thrift' library. Previously, our custom-built package was being installed in the PMon container and host OS. However, we are only building a Python 2 version of that package, which was only intended for use with saithrift.
Fixes#6077
Submodule updates include the following commits:
* src/sonic-utilities 9dc58ea...f9eb739 (18):
> Remove unnecessary calls to str.encode() now that the package is Python 3; Fix deprecation warning (#1260)
> [generate_dump] Ignoring file/directory not found Errors (#1201)
> Fixed porstat rate and util issues (#1140)
> fix error: interface counters is mismatch after warm-reboot (#1099)
> Remove unnecessary calls to str.decode() now that the package is Python 3 (#1255)
> [acl-loader] Make list sorting compliant with Python 3 (#1257)
> Replace hard-coded fast-reboot with variable. And some typo corrections (#1254)
> [configlet][portconfig] Remove calls to dict.has_key() which is not available in Python 3 (#1247)
> Remove unnecessary conversions to list() and calls to dict.keys() (#1243)
> Clean up LGTM alerts (#1239)
> Add 'requests' as install dependency in setup.py (#1240)
> Convert to Python 3 (#1128)
> Fix mock SonicV2Connector in python3: use decode_responses mode so caller code will be the same as python2 (#1238)
> [tests] Do not trim from PATH if we did not append to it; Clean up/fix shebangs in scripts (#1233)
> Updates to bgp config and show commands with BGP_INTERNAL_NEIGHBOR table (#1224)
> [cli]: NAT show commands newline issue after migrated to Python3 (#1204)
> [doc]: Update Command-Reference.md (#1231)
> Added 'import sys' in feature.py file (#1232)
* src/sonic-py-swsssdk 9d9f0c6...1664be9 (2):
> Fix: no need to decode() after redis client scan, so it will work for both python2 and python3 (#96)
> FieldValueMap `contains`(`in`) will also work when migrated to libswsscommon(C++ with SWIG wrapper) (#94)
- Also fix Python 3-related issues:
- Use integer (floor) division in config_samples.py (sonic-config-engine)
- Replace print statement with print function in eeprom.py plugin for x86_64-kvm_x86_64-r0 platform
- Update all platform plugins to be compatible with both Python 2 and Python 3
- Remove shebangs from plugins files which are not intended to be executable
- Replace tabs with spaces in Python plugin files and fix alignment, because Python 3 is more strict
- Remove trailing whitespace from plugins files
- Why I did it
Add reboot history to State db so that can be used telemetry service
- How I did it
Split the process-reboot-cause service to determine-reboot-cause and process-reboot-cause
determine-reboot-cause to determine the reboot cause
process-reboot-cause to parse the reboot cause files and put the reboot history to state db
Moved to sonic-host-service* packages
- How to verify it
Performed unit test and tested on DUT
Summary: Move teamd functions to a new service script
Motivation: To segregate teamd functions in one common place. fast-reboot script calls teamd functions that should ideally be replaced by a simple call to a service script.
Changes: New teamd service script and path modification from /usr/bin/teamd.sh to /usr/local/bin/teamd.sh
fast-reboot script (in sonic-utilities) modification (to use new teamd.sh to stop teamd) should follow soon after this change.
Verification: VS image tests.
Signed-off-by: Vaibhav Hemant Dixit <vaibhav.dixit@microsoft.com>
Co-authored-by: heidi.ou@alibaba-inc.com <heidi.ou@alibaba-inc.com>
Co-authored-by: Ying Xie <ying.xie@microsoft.com>
This change introduces PDDF which is described here: https://github.com/Azure/SONiC/pull/536
Most of the platform bring up effort goes in developing the platform device drivers, SONiC platform APIs and validating them. Typically each platform vendor writes their own drivers and platform APIs which is very tailor made to that platform. This involves writing code, building, installing it on the target platform devices and testing. Many of the details of the platform are hard coded into these drivers, from the HW spec. They go through this cycle repetitively till everything works fine, and is validated before upstreaming the code.
PDDF aims to make this platform driver and platform APIs development process much simpler by providing a data driven development framework. This is enabled by:
JSON descriptor files for platform data
Generic data-driven drivers for various devices
Generic SONiC platform APIs
Vendor specific extensions for customisation and extensibility
Signed-off-by: Fuzail Khan <fuzail.khan@broadcom.com>
To consolidate host services and install via packages instead of file-by-file, also as part of migrating all of SONiC to Python 3, as Python 2 is no longer supported.
- Convert core_uploader.py script to Python 3
- Use logger from sonic-py-common for uniform logging
- Reorganize imports alphabetically per PEP8 standard
- Two blank lines precede functions per PEP8 standard
- Remove unnecessary global variable declarations
* Build and install openssh from source
* Copy openssh deb package to dest folder
* Update make rule
* Update sonic debian extension
* Append empty line before EOF
* Update openssh patch
* Add openssh-server to base image dependency
* Fix indent type
* Fix comments
* Use commit id instead of tag id and add comment
Signed-off-by: Jing Kan jika@microsoft.com
As part of the transition from Python 2 to Python 3, we are installing both pip2 and pip3 in the slave and config-engine containers. This PR replaces calls to `pip` in these containers with an explicit call to `pip2` to ensure the proper version of pip is executed, no matter which version of pip is aliased to `pip`, as we no longer rely on that alias.
Also some other pip-related cleanup
To consolidate host services and install via packages instead of file-by-file, also as part of migrating all of SONiC to Python 3, as Python 2 is no longer supported, convert caclmgrd to Python 3 and add to sonic-host-services package
**- Why I did it**
Install all host services and their data files in package format rather than file-by-file
**- How I did it**
- Create sonic-host-services Python wheel package, currently including procdockerstatsd
- Also add the framework for unit tests by adding one simple procdockerstatsd test case
- Create sonic-host-services-data Debian package which is responsible for installing the related systemd unit files to control the services in the Python wheel. This package will also be responsible for installing any Jinja2 templates and other data files needed by the host services.
bring up chassisdb service on sonic switch according to the design in
Distributed Forwarding in VoQ Arch HLD
Signed-off-by: Honggang Xu <hxu@arista.com>
**- Why I did it**
To bring up new ChassisDB service in sonic as designed in ['Distributed forwarding in a VOQ architecture HLD' ](90c1289eaf/doc/chassis/architecture.md).
**- How I did it**
Implement the section 2.3.1 Global DB Organization of the VOQ architecture HLD.
**- How to verify it**
ChassisDB service won't start without chassisdb.conf file on the existing platforms.
ChassisDB service is accessible with global.conf file in the distributed arichitecture.
Signed-off-by: Honggang Xu <hxu@arista.com>
We were building our own python-click package because we needed features/bug fixes available as of version 7.0.0, but the most recent version available from Debian was in the 6.x range.
"Click" is needed for building/testing and installing sonic-utilities. Now that we are building sonic-utilities as a wheel, with Click specified as a dependency in the setup.py file, setuptools will install a more recent version of Click in the sonic-slave-buster container when building the package, and pip will install a more recent version of Click in the host OS of SONiC when installing the sonic-utilities package. Also, we don't need to worry about installing the Python 2 or 3 version of the package, as the proper one will be installed as necessary.
* system health first commit
* system health daemon first commit
* Finish healthd
* Changes due to lower layer logic change
* Get ASIC temperature from TEMPERATURE_INFO table
* Add system health make rule and service files
* fix bugs found during manual test
* Change make file to install system-health library to host
* Set system LED to blink on bootup time
* Caught exceptions in system health checker to make it more robust
* fix issue that fan/psu presence will always be true
* fix issue for external checker
* move system-health service to right after rc-local service
* Set system-health service start after database service
* Get system up time via /proc/uptime
* Provide more information in stat for CLI to use
* fix typo
* Set default category to External for external checker
* If external checker reported OK, save it to stat too
* Trim string for external checker output
* fix issue: PSU voltage check always return OK
* Add unit test cases for system health library
* Fix LGTM warnings
* fix demo comments: 1. get boot up timeout from monit configuration file; 2. set system led in library instead of daemon
* Remove boot_timeout configuration because it will get from monit config file
* Fix argument miss
* fix unit test failure
* fix issue: summary status is not correct
* Fix format issues found in code review
* rename th to threshold to make it clearer
* Fix review comment: 1. add a .dep file for system health; 2. deprecated daemon_base and uses sonic-py-common instead
* Fix unit test failure
* Fix LGTM alert
* Fix LGTM alert
* Fix review comments
* Fix review comment
* 1. Add relevant comments for system health; 2. rename external_checker to user_define_checker
* Ignore check for unknown service type
* Fix unit test issue
* Rename user define checker to user defined checker
* Rename user_define_checkers to user_defined_checkers for configuration file
* Renmae file user_define_checker.py -> user_defined_checker.py
* Fix typo
* Adjust import order for config.py
Co-authored-by: Joe LeVeque <jleveque@users.noreply.github.com>
* Adjust import order for src/system-health/health_checker/hardware_checker.py
Co-authored-by: Joe LeVeque <jleveque@users.noreply.github.com>
* Adjust import order for src/system-health/scripts/healthd
Co-authored-by: Joe LeVeque <jleveque@users.noreply.github.com>
* Adjust import orders in src/system-health/tests/test_system_health.py
* Fix typo
* Add new line after import
* If system health configuration file not exist, healthd should exit
* Fix indent and enable pytest coverage
* Fix typo
* Fix typo
* Remove global logger and use log functions inherited from super class
* Change info level logger to notice level
Co-authored-by: Joe LeVeque <jleveque@users.noreply.github.com>
* buildimage: Add gearbox phy device files and a new physyncd docker to support VS gearbox phy feature
* scripts and configuration needed to support a second syncd docker (physyncd)
* physyncd supports gearbox device and phy SAI APIs and runs multiple instances of syncd, one per phy in the device
* support for VS target (sonic-sairedis vslib has been extended to support a virtual BCM81724 gearbox PHY).
HLD is located at b817a12fd8/doc/gearbox/gearbox_mgr_design.md
**- Why I did it**
This work is part of the gearbox phy joint effort between Microsoft and Broadcom, and is based
on multi-switch support in sonic-sairedis.
**- How I did it**
Overall feature was implemented across several projects. The collective pull requests (some in late stages of review at this point):
https://github.com/Azure/sonic-utilities/pull/931 - CLI (merged)
https://github.com/Azure/sonic-swss-common/pull/347 - Minor changes (merged)
https://github.com/Azure/sonic-swss/pull/1321 - gearsyncd, config parsers, changes to orchargent to create gearbox phy on supported systems
https://github.com/Azure/sonic-sairedis/pull/624 - physyncd, virtual BCM81724 gearbox phy added to vslib
**- How to verify it**
In a vslib build:
root@sonic:/home/admin# show gearbox interfaces status
PHY Id Interface MAC Lanes MAC Lane Speed PHY Lanes PHY Lane Speed Line Lanes Line Lane Speed Oper Admin
-------- ----------- --------------- ---------------- --------------- ---------------- ------------ ----------------- ------ -------
1 Ethernet48 121,122,123,124 25G 200,201,202,203 25G 204,205 50G down down
1 Ethernet49 125,126,127,128 25G 206,207,208,209 25G 210,211 50G down down
1 Ethernet50 69,70,71,72 25G 212,213,214,215 25G 216 100G down down
In addition, docker ps | grep phy should show a physyncd docker running.
Signed-off-by: syd.logan@broadcom.com
We want to let Monit to unmonitor the processes in containers which are disabled in `FEATURE` table such that
Monit will not generate false alerting messages into the syslog.
Signed-off-by: Yong Zhao <yozhao@microsoft.com>
We are moving toward building all Python packages for SONiC as wheel packages rather than Debian packages. This will also allow us to more easily transition to Python 3.
Python files are now packaged in "sonic-utilities" Pyhton wheel. Data files are now packaged in "sonic-utilities-data" Debian package.
**- How I did it**
- Build and install sonic-utilities as a Python package
- Remove explicit installation of wheel dependencies, as these will now get installed implicitly by pip when installing sonic-utilities as a wheel
- Build and install new sonic-utilities-data package to install data files required by sonic-utilities applications
- Update all references to sonic-utilities scripts/entrypoints to either reference the new /usr/local/bin/ location or remove absolute path entirely where applicable
Submodule updates:
* src/sonic-utilities aa27dd9...2244d7b (5):
> Support building sonic-utilities as a Python wheel package instead of a Debian package (#1122)
> [consutil] Display remote device name in show command (#1120)
> [vrf] fix check state_db error when vrf moving (#1119)
> [consutil] Fix issue where the ConfigDBConnector's reference is missing (#1117)
> Update to make config load/reload backward compatible. (#1115)
* src/sonic-ztp dd025bc...911d622 (1):
> Update paths to reflect new sonic-utilities install location, /usr/local/bin/ (#19)
Introduced a new build parameter 'SONIC_IMAGE_VERSION' that allows build
system users to build SONiC image with a specific version string. If
'SONIC_IMAGE_VERSION' was not passed by the user, SONIC_IMAGE_VERSION will be
set to the output of functions.sh:sonic_get_version function.
Signed-off-by: Stepan Blyschak <stepanb@nvidia.com>
management framework provides management plane services like rest and
CLI which is not needed right after boot, instead by delaying this
service we give some more CPU for data plane and control plane services
on fast/warm boot.
Signed-off-by: Stepan Blyschak <stepanb@nvidia.com>
- Why I did it
When SONiC is configured with the management framework and/or telemetry services, the applications running inside those containers need to access some functionality on the host system. The following is a non-exhaustive list of such functionality:
Image management
Configuration save and load
ZTP enable/disable and status
Show tech support
- How I did it
The host service is a Python process that listens for requests via D-Bus. It will then service those requests and send a response back to the requestor.
This PR only introduces the host service infrastructure. Applications that need access to the host services must add applets that will register on D-Bus endpoints to service the appropriate functionality.
- How to verify it
- Description for the changelog
Add SONiC Host Service for container to execute select commands in host
Signed-off-by: Nirenjan Krishnan <Nirenjan.Krishnan@dell.com>
* Support for Control Plane ACL's for Multi-asic Platforms.
Following changes were done:
1) Moved from using blocking listen() on Config DB to the select() model
via python-swsscommon since we have to wait on event from multiple
config db's
2) Since python-swsscommon is not available on host added libswsscommon and python-swsscommon
and dependent packages in the base image (host enviroment)
3) Made iptables programmed in all namespace using ip netns exec
Signed-off-by: Abhishek Dosi <abdosi@microsoft.com>
* Address Review Comments
Signed-off-by: Abhishek Dosi <abdosi@microsoft.com>
* Fix Review Comments
* Fix Comments
* Added Change for Multi-asic to have iptables
rules to accept internal docker tcp/udp traffic
needed for syslog and redis-tcp connection.
Signed-off-by: Abhishek Dosi <abdosi@microsoft.com>
* Fix Review Comments
* Added more comments on logic.
* Fixed all warning/errors reported by http://pep8online.com/
other than line > 80 characters.
* Fix Comment
Signed-off-by: Abhishek Dosi <abdosi@microsoft.com>
* Verified with swsscommon package. Fix issue for single asic platforms.
* Moved to new python package
* Address Review Comments.
Signed-off-by: Abhishek Dosi <abdosi@microsoft.com>
* Address Review Comments.
Removes installation of kube-proxy (117 MB) and flannel (53 MB) images from Kubernetes-enabled devices. These images are tested to be unnecessary for our use case, as we do not rely on ClusterIPs for Kubernetes Services or a CNI for pod networking.
1. remove container feature table
2. do not generate feature entry if the feature is not included
in the image
3. rename ENABLE_* to INCLUDE_* for better clarity
4. rename feature status to feature state
5. [submodule]: update sonic-utilities
* 9700e45 2020-08-03 | [show/config]: combine feature and container feature cli (#1015) (HEAD, origin/master, origin/HEAD) [lguohan]
* c9d3550 2020-08-03 | [tests]: fix drops_group_test failure on second run (#1023) [lguohan]
* dfaae69 2020-08-03 | [lldpshow]: Fix input device is not a TTY error (#1016) [Arun Saravanan Balachandran]
* 216688e 2020-08-02 | [tests]: rename sonic-utilitie-tests to tests (#1022) [lguohan]
Signed-off-by: Guohan Lu <lguohan@gmail.com>
As part of consolidating all common Python-based functionality into the new sonic-py-common package, this pull request:
1. Redirects all Python applications/scripts in sonic-buildimage repo which previously imported sonic_device_util or sonic_daemon_base to instead import sonic-py-common, which was added in https://github.com/Azure/sonic-buildimage/pull/5003
2. Replaces all calls to `sonic_device_util.get_platform_info()` to instead call `sonic_py_common.get_platform()` and removes any calls to `sonic_device_util.get_machine_info()` which are no longer necessary (i.e., those which were only used to pass the results to `sonic_device_util.get_platform_info()`.
3. Removes unused imports to the now-deprecated sonic-daemon-base package and sonic_device_util.py module
This is the next step toward resolving https://github.com/Azure/sonic-buildimage/issues/4999
Also reverted my previous change in which device_info.get_platform() would first try obtaining the platform ID string from Config DB and fall back to gathering it from machine.conf upon failure because this function is called by sonic-cfggen before the data is in the DB, in which case, the db_connect() call will hang indefinitely, which was not the behavior I expected. As of now, the function will always reference machine.conf.
