Configuration Management
SONiC manages configuration in a RedisDB instance called ConfigDB. The ConfigDB acts as a single source of truth for SONiC configuration (https://github.com/sonic-net/sonic-buildimage/blob/master/src/sonic-yang-models/doc/Configuration.md)
The SONiC configuration is represented in a .json file located at /etc/sonic/config_db.json. When the device boots up, SONiC loads the startup configuration from /etc/sonic/config_db.json into the Redis ConfigDB and configures the device.
It is important to note that subsequent changes in the Redis ConfigDB are not automatically written into /etc/sonic/config_db.json. Instead, a user can initiate a write by issuing a sudo config save -y command.
Configuration actions can be performed using one of these methods:
- Command Line Interface (CLI) commands in the Linux shell
- Using JSON files
- vty shell in FRR
CLI commands
Configuration commands
These commands are used to modify the configuration of the device. Configuration commands begin with the config keyword and can be used to configure various router parameters, such as interface configuration, routes, and ACLs.
These commands must be executed with root privileges by using sudo.
Configuration commands directly change the state of the ConfigDB in the Redis container in SONiC. To ensure the configuration state persists across reboots, update the /etc/sonic/config_db.json file using the sudo config save -y command.
For example, to set the hostname of the device:
admin@sonic:~$ sudo hostname R1
Save this configuration using the config save command.
admin@R1:~$ sudo config save -y
Running command: /usr/local/bin/sonic-cfggen -d --print-data > /etc/sonic/config_db.json
admin@R1:~$
Show commands
Show commands are used to display the device's operational state and associated data and begin with the show keyword. Unlike configuration commands, most of these commands can be executed by the default user.
Useful show commands
- View the interface summary of the device using the
show interfaces statuscommand.
admin@sonic:~$ show interfaces status
Interface Lanes Speed MTU FEC Alias Vlan Oper Admin Type Asym PFC
----------- --------------------------------------- ------- ----- ----- ------- ------ ------ ------- ------ ----------
Ethernet0 2304,2305,2306,2307,2308,2309,2310,2311 400G 9100 N/A etp0 routed up up N/A N/A
Ethernet8 2320,2321,2322,2323,2324,2325,2326,2327 400G 9100 N/A etp1 routed up up N/A N/A
Ethernet16 2312,2313,2314,2315,2316,2317,2318,2319 400G 9100 N/A etp2 routed up up N/A N/A
Ethernet24 2056,2057,2058,2059,2060,2061,2062,2063 400G 9100 N/A etp3 routed up up N/A N/A
Ethernet32 1792,1793,1794,1795,1796,1797,1798,1799 400G 9100 N/A etp4 routed up up N/A N/A
Ethernet40 2048,2049,2050,2051,2052,2053,2054,2055 400G 9100 N/A etp5 routed up up N/A N/A
Ethernet48 2560,2561,2562,2563,2564,2565,2566,2567 400G 9100 N/A etp6 routed up up N/A N/A
Ethernet56 2824,2825,2826,2827,2828,2829,2830,2831 400G 9100 N/A etp7 routed up up N/A N/A
Ethernet64 2832,2833,2834,2835,2836,2837,2838,2839 400G 9100 N/A etp8 routed up up N/A N/A
Ethernet72 2816,2817,2818,2819,2820,2821,2822,2823 400G 9100 N/A etp9 routed up up N/A N/A
Ethernet80 2568,2569,2570,2571,2572,2573,2574,2575 400G 9100 N/A etp10 routed up up N/A N/A
Ethernet88 2576,2577,2578,2579,2580,2581,2582,2583 400G 9100 N/A etp11 routed up up N/A N/A
Ethernet96 1536,1537,1538,1539,1540,1541,1542,1543 400G 9100 N/A etp12 routed up up N/A N/A
Ethernet104 1800,1801,1802,1803,1804,1805,1806,1807 400G 9100 N/A etp13 routed up up N/A N/A
Ethernet112 1552,1553,1554,1555,1556,1557,1558,1559 400G 9100 N/A etp14 routed up up N/A N/A
Ethernet120 1544,1545,1546,1547,1548,1549,1550,1551 400G 9100 N/A etp15 routed up up N/A N/A
Ethernet128 1296,1297,1298,1299,1300,1301,1302,1303 400G 9100 N/A etp16 routed up up N/A N/A
Ethernet136 1288,1289,1290,1291,1292,1293,1294,1295 400G 9100 N/A etp17 routed up up N/A N/A
Ethernet144 1280,1281,1282,1283,1284,1285,1286,1287 400G 9100 N/A etp18 routed up up N/A N/A
Ethernet152 1032,1033,1034,1035,1036,1037,1038,1039 400G 9100 N/A etp19 routed up up N/A N/A
Ethernet160 264,265,266,267,268,269,270,271 400G 9100 N/A etp20 routed up up N/A N/A
Ethernet168 272,273,274,275,276,277,278,279 400G 9100 N/A etp21 routed up up N/A N/A
Ethernet176 16,17,18,19,20,21,22,23 400G 9100 N/A etp22 routed up up N/A N/A
Ethernet184 0,1,2,3,4,5,6,7 400G 9100 N/A etp23 routed up up N/A N/A
Ethernet192 256,257,258,259,260,261,262,263 400G 9100 N/A etp24 routed up up N/A N/A
Ethernet200 8,9,10,11,12,13,14,15 400G 9100 N/A etp25 routed up up N/A N/A
Ethernet208 1024,1025,1026,1027,1028,1029,1030,1031 400G 9100 N/A etp26 routed up up N/A N/A
Ethernet216 768,769,770,771,772,773,774,775 400G 9100 N/A etp27 routed up up N/A N/A
Ethernet224 520,521,522,523,524,525,526,527 400G 9100 N/A etp28 routed up up N/A N/A
Ethernet232 776,777,778,779,780,781,782,783 400G 9100 N/A etp29 routed up up N/A N/A
Ethernet240 512,513,514,515,516,517,518,519 400G 9100 N/A etp30 routed up up N/A N/A
Ethernet248 528,529,530,531,532,533,534,535 400G 9100 N/A etp31 routed up up N/A N/A
- View the platform specific information using the
show platformcommands.
admin@sonic:~$ show platform -h
Usage: show platform [OPTIONS] COMMAND [ARGS]...
Show platform-specific hardware info
Options:
-h, -?, --help Show this message and exit.
Commands:
current Show device current information
eth-switch Show ethernet switch information
fabric Show platform fabric
fan Show fan status information
firmware Show firmware information
idprom Show Platform Idprom Inventory
inventory Show Platform inventory
npu Show NPU
obfl Show Platform obfl logging
pcieinfo Show Device PCIe Info
psustatus Show PSU status information
rdma-config Show Platform RDMA config
ssdhealth Show SSD Health information
summary Show hardware platform information
syseeprom Show system EEPROM information
temperature Show device temperature information
versions
voltage Show device voltage information
- View the fan status using the
show platform fancommand:
admin@sonic:~$ show platform fan
Drawer LED FAN Speed Direction Presence Status Timestamp
-------- ----- ------------- ------- ----------- ---------- -------- -----------------
N/A N/A PSU0.fan0 50% N/A Present OK 20241210 03:00:33
N/A N/A PSU1.fan0 50% N/A Present OK 20241210 03:00:33
fantray0 green fantray0.fan0 26% intake Present OK 20241210 03:00:31
fantray0 green fantray0.fan1 28% intake Present OK 20241210 03:00:31
fantray1 green fantray1.fan0 26% intake Present OK 20241210 03:00:31
fantray1 green fantray1.fan1 27% intake Present OK 20241210 03:00:31
fantray2 green fantray2.fan0 26% intake Present OK 20241210 03:00:32
fantray2 green fantray2.fan1 27% intake Present OK 20241210 03:00:32
fantray3 green fantray3.fan0 25% intake Present OK 20241210 03:00:32
fantray3 green fantray3.fan1 27% intake Present OK 20241210 03:00:32
fantray4 green fantray4.fan0 26% intake Present OK 20241210 03:00:32
fantray4 green fantray4.fan1 27% intake Present OK 20241210 03:00:32
fantray5 green fantray5.fan0 25% intake Present OK 20241210 03:00:32
fantray5 green fantray5.fan1 28% intake Present OK 20241210 03:00:32
- View the PSU status using the
show platform psustatuscommand:
admin@sonic:~$ show platform psustatus
PSU Model Serial HW Rev Voltage (V) Current (A) Power (W) Status LED
----- ------------- ----------- -------- ------------- ------------- ----------- -------- -----
PSU 1 PSU1.4KW-ACPI XXXXXXXXXXX 0.00 N/A N/A N/A NOT OK amber
PSU 2 PSU1.4KW-ACPI XXXXXXXXXXX 0.00 12.001 23.0 275.5 OK green
- Additionally, while the SONiC startup configuration can be accessed through
/etc/config_db.json, the simplest way to get the running configuration is through the CLI with theshow runningconfigurationcommand. You can choose to view the entire configuration or a specific subsection, as shown in this example.
admin@sonic:~$ show runningconfiguration -h
Usage: show runningconfiguration [OPTIONS] COMMAND [ARGS]...
Show current running configuration information
Options:
-?, -h, --help Show this message and exit.
Commands:
acl Show acl running configuration
all Show full running configuration
bgp Show BGP running configuration Note: multi-asic can run 'show...
interfaces Show interfaces running configuration
ntp Show NTP running configuration
ports Show ports running configuration
snmp Show SNMP running configuration
syslog Show Syslog running configuration
JSON files
Configuration can also be applied using JSON files. You can specify configuration items as per SONiC JSON configuration schema in a json file and apply it. You can apply these configurations in two ways:
Apply JSONs using config load or config reload
- You can apply JSON configuration using the
config loadcommand. This command attempts to add to the running configuration or modify the parameters in the running configuration. This command cannot remove existing configuration and can only be used to add or modify the configuration. It can be used in two ways:
config load <target_config.json>
In this case the contents of target_config.json will be added to the running configuration.
config load
In this case, the contents of /etc/sonic/config_db.json will be added to the running configuration.
For example:
admin@sonic:~$ vim ip_config.json
admin@sonic:~$ cat ip_config.json
{
"INTERFACE": {
"Ethernet0": {},
"Ethernet0|192.1.2.2/30": {},
"Ethernet8": {},
"Ethernet8|192.1.2.6/30": {},
"Ethernet16": {},
"Ethernet16|192.1.2.10/30": {},
"Ethernet24": {},
"Ethernet24|192.1.2.14/30": {}
},
"MGMT_INTERFACE": {
"eth0|192.168.1.2/16": {
"gwaddr": "192.168.0.1"
}
}
}
admin@sonic:~$ sudo config load
Load config from the default config file(s) ? [y/N]: y
Running command: /usr/local/bin/sonic-cfggen -j /etc/sonic/config_db.json --write-to-db
admin@sonic:~$ show ip interfaces
Interface Master IPv4 address/mask Admin/Oper BGP Neighbor Neighbor IP
----------- -------- ------------------- ------------ -------------- -------------
Ethernet0 192.1.2.2/30 up/down N/A N/A
Ethernet8 192.1.2.6/30 up/down N/A N/A
Ethernet16 192.1.2.10/30 up/down N/A N/A
Ethernet24 192.1.2.14/30 up/down N/A N/A
docker0 240.127.1.1/24 up/down N/A N/A
eth0 192.168.1.2/16 up/up N/A N/A
lo 127.0.0.1/16 up/up N/A N/A
admin@sonic:~$
- Alternatively, you can use the
config reloadcommand. This command clears all the contents of the redis ConfigDB and loads the contents of specified json file into the redis ConfigDB. This command can be used in two ways as well:
It can be used in two ways:
- In this first method the content of target_config.json will replace the running configuration.
admin@sonic:~$ config reload <target_config.json>
- In the second method, the contents of
/etc/sonic/config_db.jsonwill replace the running configuration.
admin@sonic:~$ config reload
sonic-cfggen
The sonic-cfggen is a utility to read SONiC config from various input types and then write the config to the config database in Redis, print as a JSON or render a jinja2 config template.
To configure the device, sonic-cfggen can be used to make changes directly to the running configuration. sonic-cfggen validates adherence to the standard json schema but does not validate configDB parameters.
For example, the following workflow sets the IP addresses of several interfaces at once defined in the ip_config.json file:
root@R1:/home/cisco# cat ip_config.json
{
"INTERFACE": {
"Ethernet0": {},
"Ethernet0|192.1.2.2/30": {},
"Ethernet8": {},
"Ethernet8|192.1.2.6/30": {},
"Ethernet16": {},
"Ethernet16|192.1.2.10/30": {},
"Ethernet24": {},
"Ethernet24|192.1.2.14/30": {}
},
"MGMT_INTERFACE": {
"eth0|192.168.1.2/16": {
"gwaddr": "192.168.0.1"
}
}
}
root@R1:/home/cisco# sonic-cfggen -j ip_config.json --write-to-db
To verify that our changes were successfully applied:
root@R1:/home/cisco# show ip interfaces
Interface Master IPv4 address/mask Admin/Oper BGP Neighbor Neighbor IP
----------- -------- ------------------- ------------ -------------- -------------
Ethernet0 192.1.2.2/30 up/down N/A N/A
Ethernet8 192.1.2.6/30 up/down N/A N/A
Ethernet16 192.1.2.10/30 up/down N/A N/A
Ethernet24 192.1.2.14/30 up/down N/A N/A
docker0 240.127.1.1/24 up/down N/A N/A
eth0 192.168.1.2/16 up/up N/A N/A
lo 127.0.0.1/16 up/up N/A N/A
root@R1:/home/cisco#
To save our changes to the /etc/sonic/config_db.json file (to persist changes across reboots)
config save -y
vty shell in FRR
SONiC uses FRR as for it's routing stack. FRR runs as a docker container on SONiC and has an interactive shell that can be used to configure routing parameters. This interactive shell is a vty shell and it functions as FRR's command line interface (CLI).
Execute the command to drop into the vty shell.
vtysh
For example:
admin@sonic:~$ vtysh
Hello, this is FRRouting (version 8.5.1).
Copyright 1996-2005 Kunihiro Ishiguro, et al.
sonic#
From this vty shell, you can execute commands, configure routing protocols as well and get operational data about the routing state.
For example, to configure a BGP Autonomous System and a neighbor:
root@sonic:/home/admin# vtysh
Hello, this is FRRouting (version 8.5.1).
Copyright 1996-2005 Kunihiro Ishiguro, et al.
sonic# configure
sonic(config)# router bgp 65000
sonic(config-router)# neighbor 10.10.10.1 remote-as 65000
sonic(config-router)#
And to view BGP summary from the vty shell:
root@sonic:/home/admin# vtysh
Hello, this is FRRouting (version 8.5.1).
Copyright 1996-2005 Kunihiro Ishiguro, et al.
sonic# show bgp summary
IPv4 Unicast Summary (VRF default):
BGP router identifier 1.1.1.1, local AS number 65000 vrf-id 0
BGP table version 0
RIB entries 0, using 0 bytes of memory
Peers 1, using 725 KiB of memory
Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd PfxSnt Desc
10.10.10.1 4 65000 0 0 0 0 0 never Connect 0 N/A
Total number of neighbors 1
sonic#