FWA-1012VC network port naming issue in Ubuntu

Purpose

The Ethernet port naming would be different on different OS distributions ,  most of the naming will easy to understand (expected) but some of them are not. 

This FAQ shows a case in ubuntu that some of Ethernet ports were named as "renameX" which are unexpected from our experiences.  The root cause here is the duplicated  “Type Instance” from “dmidecode -t 41” ,  even thought the  “Type Instance” may not be unique, but there's still an instruction to have OS rename Ethnet ports as expected. 

Target Audience

For users who are running ubuntu OS on FWA-1012VC

Checks

Default naming in Ubuntu OS would be as in below

eth0 = eno1
eth1 = rename3
eth2 = rename4
eth3 = rename5
eth4 = rename6
eth5 = rename7

## Root Cause (Should be improved with latest BIOS updated)

According to dmesg , OS renamed the Ethernet devices because “Type Instance” from “dmidecode -t 41” is NOT unique.

* dmi type 41 is pointed to on-board device for NID utility in future ENPD products

##

Unique Type Instance in DMI type 41 will be implemented in most of New BIOS release , this issue would be prevented. Please contact HQ for understanding on this implementations.

Even though the “Type Instance” would lead in issue on Ubuntu , there’s still an workaround (instruction) to make Eth devices more meaningful/readable in below. This instruction is leveraged the “label” info from the DMI and apply to the rule we created.   

1. Create net rules as “/etc/udev/rules.d/70-persistent-net.rules”
2. Adding a line SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", NAME="%s{label}" in “/etc/udev/rules.d/70-persistent-net.rules”
3. Reboot and check devices list

        * Also attached rule from my OS as reference.

New list would be

# ip link show

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1

    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00

2: mgmt0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN mode DEFAULT group default qlen 1000

    link/ether c4:00:ad:a3:b5:c4 brd ff:ff:ff:ff:ff:ff

3: mgmt1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DEFAULT group default qlen 1000

    link/ether c4:00:ad:a3:b5:c5 brd ff:ff:ff:ff:ff:ff

4: lan0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN mode DEFAULT group default qlen 1000

    link/ether 00:a0:c9:00:00:00 brd ff:ff:ff:ff:ff:ff

5: wan0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN mode DEFAULT group default qlen 1000

    link/ether 34:12:78:56:01:01 brd ff:ff:ff:ff:ff:ff

6: lan1: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN mode DEFAULT group default qlen 1000

    link/ether 00:a0:c9:00:00:02 brd ff:ff:ff:ff:ff:ff

7: wan1: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN mode DEFAULT group default qlen 1000

    link/ether 34:12:78:56:01:03 brd ff:ff:ff:ff:ff:ff

8: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN mode DEFAULT group default qlen 1000

    link/ether 52:54:00:b6:56:5d brd ff:ff:ff:ff:ff:ff

9: virbr0-nic: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast master virbr0 state DOWN mode DEFAULT group default qlen 1000