SNMP: IfIndex MIB [RFC 1213] starts from 0

[nmoray-ebay]

Description

The Interface index MIB [OID:1.3.6.1.2.1.2.2.1.1] in SONiC starts from 0. As per RFC 1213, the IfIndex should be ranging from 1 to the value of ifNumber.

Steps to reproduce the issue:

1. Do a snmpwalk for OID: 1.3.6.1.2.1.2.2.1.1
2. Check the IfIndex mapping. It starts from 0.

Describe the results you received:

root@SN2100-Leaf1:/# snmpwalk -v2c -c public localhost 1.3.6.1.2.1.2.2.1.1
iso.3.6.1.2.1.2.2.1.1.1 = INTEGER: 0
iso.3.6.1.2.1.2.2.1.1.5 = INTEGER: 4
iso.3.6.1.2.1.2.2.1.1.9 = INTEGER: 8
iso.3.6.1.2.1.2.2.1.1.13 = INTEGER: 12
iso.3.6.1.2.1.2.2.1.1.17 = INTEGER: 16
iso.3.6.1.2.1.2.2.1.1.21 = INTEGER: 20
iso.3.6.1.2.1.2.2.1.1.25 = INTEGER: 24

Describe the results you expected:

iso.3.6.1.2.1.2.2.1.1.1 = INTEGER: 1
iso.3.6.1.2.1.2.2.1.1.5 = INTEGER: 5
iso.3.6.1.2.1.2.2.1.1.9 = INTEGER: 9
iso.3.6.1.2.1.2.2.1.1.13 = INTEGER: 13
iso.3.6.1.2.1.2.2.1.1.17 = INTEGER: 17
iso.3.6.1.2.1.2.2.1.1.21 = INTEGER: 21
iso.3.6.1.2.1.2.2.1.1.25 = INTEGER: 25

Output of show version:

SONiC Software Version: SONiC.202111.0-dirty-20221010.231127
Distribution: Debian 11.5
Kernel: 5.10.0-8-2-amd64
Build commit: ec691aa9f
Build date: Tue Oct 11 07:54:06 UTC 2022
Built by: kuldip.patel@aviz01

Platform: x86_64-mlnx_msn2100-r0
HwSKU: ACS-MSN2100
ASIC: mellanox
ASIC Count: 1
Serial Number: MT1950X05002
Model Number: MSN2100-CB2FO
Hardware Revision: A2
Uptime: 02:17:01 up 1 day,  3:46,  1 user,  load average: 0.24, 0.25, 0.45

Docker images:
REPOSITORY                    TAG                              IMAGE ID       SIZE
avizdock/ones-agent           v1.0.0                           5a2603b6a936   645MB
docker-dhcp-relay             latest                           890165d1d890   442MB
docker-teamd                  202111.0-dirty-20221010.231127   9e11eeacb228   443MB
docker-teamd                  latest                           9e11eeacb228   443MB
docker-syncd-mlnx             202111.0-dirty-20221010.231127   27f47464cdb1   928MB
docker-syncd-mlnx             latest                           27f47464cdb1   928MB
docker-sonic-telemetry        202111.0-dirty-20221010.231127   25aadf90f50c   517MB
docker-sonic-telemetry        latest                           25aadf90f50c   517MB
docker-sonic-mgmt-framework   202111.0-dirty-20221010.231127   843df6f803e6   585MB
docker-sonic-mgmt-framework   latest                           843df6f803e6   585MB
docker-snmp                   202111.0-dirty-20221010.231127   46007feaed7f   472MB
docker-snmp                   latest                           46007feaed7f   472MB
docker-sflow                  202111.0-dirty-20221010.231127   e89436c8880a   443MB
docker-sflow                  latest                           e89436c8880a   443MB
docker-router-advertiser      202111.0-dirty-20221010.231127   5df23e70624a   428MB
docker-router-advertiser      latest                           5df23e70624a   428MB
docker-platform-monitor       202111.0-dirty-20221010.231127   fe3e4ad48b2f   820MB
docker-platform-monitor       latest                           fe3e4ad48b2f   820MB
docker-orchagent              202111.0-dirty-20221010.231127   bf418d947316   460MB
docker-orchagent              latest                           bf418d947316   460MB
docker-nat                    202111.0-dirty-20221010.231127   291ea6094720   445MB
docker-nat                    latest                           291ea6094720   445MB
docker-mux                    202111.0-dirty-20221010.231127   b597c3040a27   481MB
docker-mux                    latest                           b597c3040a27   481MB
docker-macsec                 202111.0-dirty-20221010.231127   646a92998af7   446MB
docker-macsec                 latest                           646a92998af7   446MB
docker-lldp                   202111.0-dirty-20221010.231127   d1cf3fae008a   468MB
docker-lldp                   latest                           d1cf3fae008a   468MB
docker-fpm-frr                202111.0-dirty-20221010.231127   74a326b8bfff   461MB
docker-fpm-frr                latest                           74a326b8bfff   461MB
docker-database               202111.0-dirty-20221010.231127   19a368f709dc   428MB
docker-database               latest                           19a368f709dc   428MB

[gechiang]

@qiluo-msft please help assign someone to investigate. Thanks!

[nmoray-ebay]

@gechiang @qiluo-msft I have raised a PR to fix this issue. Please review and share your comments.