How can I setup snmp v3 in Openwrt 19.07 and 22.03?

shailesh1 · August 8, 2024, 2:37pm

Hi,
I followed some example and solution for enabling snmp v3 but could get it successful. Is there any proper doc or method to enable SNMP v3 in Openwrt 22.03 and 19.07?

brada4 · August 8, 2024, 2:54pm

Neither release is supported, type snmp in package installer.

Please connect to your OpenWrt device using ssh and copy the output of the following commands and post it here using the "Preformatted text </> " button:

Remember to redact passwords, MAC addresses and any public IP addresses you may have:

ubus call system board

shailesh1 · August 9, 2024, 7:53am

Hi Sir,

Here is the output
root@LEDE:/# ubus call system board
{
"kernel": "4.14.221",
"hostname": "LEDE",
"system": "ARMv7 Processor rev 3 (v7l)",
"model": "Bananapi BPI-R2",
"board_name": "bananapi,bpi-r2",
"release": {
"distribution": "OpenWrt",
"version": "19.07.7",
"revision": "r11306-c4a6851c72",
"target": "mediatek/mt7623",
"description": "OpenWrt 19.07.7 r11306-c4a6851c72"
}
}

And for 22.03---------
root@(none):/# ubus call system board
{
"kernel": "5.10.140",
"hostname": "HuskyRTR",
"system": "ARM926EJ-S rev 5 (v5l)",
"model": "Nuvoton NUC980 IOT V1.0",
"board_name": "spinand",
"rootfs_type": "squashfs",
"release": {
"distribution": "OpenWrt",
"version": "22.03.0",
"revision": "r19685-512e76967f",
"target": "nuc980/iotg2",
"description": "OpenWrt 22.03.0 r19685-512e76967f"
}
}

For both of them I am trying, but I could not find anyway around to setup SNMPv3, is there any way, we can add it?

brada4 · August 9, 2024, 7:58am

Out of WE I can add it right away.

Your mileage will vary with out-of-date releases.

shailesh1 · August 9, 2024, 8:40am

I already had setup for SNNP v1 and v2 but not for V3. For V3 what specific task do we need to do? Is there any openwrt document on this.

bmork · August 9, 2024, 9:23am

You will probably have more success with your next question if you take the time to describe what you have tried and how it failed instead of referring to "some example and solution"...

Anyway, I could be wrong but I don't think snmp v3 is supported on OpenWrt. There are multiple snmp implementations available. But the most likely candidate IMHO is net-snmp, and it seems to be built without openssl support:

github.com

openwrt/packages/blob/master/net/net-snmp/Makefile#L209


      
          	--with-sys-contact=root@localhost \
          	--with-sys-location=Unknown \
          	--enable-applications \
          	--disable-debugging \
          	--disable-manuals \
          	--disable-scripts \
          	--with-out-mib-modules="$(SNMP_MIB_MODULES_EXCLUDED)" \
          	--with-mib-modules="$(SNMP_MIB_MODULES_INCLUDED)" \
          	--with-out-transports="$(SNMP_TRANSPORTS_EXCLUDED)" \
          	--with-transports="$(SNMP_TRANSPORTS_INCLUDED)" \
          	--without-openssl \
          	--without-libwrap \
          	--without-mysql \
          	--without-rpm \
          	--without-zlib \
          	--with-pcre2-8 \
          	--with-nl \
          	 $(call autoconf_bool,CONFIG_IPV6,ipv6) \
          	--disable-perl-cc-checks \
          	--disable-embedded-perl \
          	--without-perl-modules

I believe openssl is a requirement for v3. Or at least for the features you're after (guessing now since you never told us why you can't just use v2c). See

github.com

net-snmp/net-snmp/blob/master/README.snmpv3

README.snmpv3
-------------
How to setup SNMPv3, a very brief document for Dave to elaborate and
do a better job on since I suck at writing documentation and he
doesn't ;-) --Wes:

Note: SHA authentication and DES/AES encryption support is only available
if you have OpenSSL installed or if you've compiled using
--with-openssl=internal.  If you use --with-openssl=internal please
read the documentation in snmplib/openssl/README for important details.

Note: encryption support now *is* enabled in the binary releases downloadable
from the net-snmp web site.

Note: this description assumes you're using the software compiled from
source, and so installed using the default prefix location (/usr/local).
If you're working with a vendor-provided system, or have configured
things with a different prefix, you'll need to adjust locations accordingly.

CREATING THE FIRST USER:

This file has been truncated. show original

If you really need v3, then I suggest upgrading to a supported OpenWrt version and build a modified version of the net-snmp package yourself.

There are earlier forum threads like

which you should have looked at first. It says pretty much the same. Now we have one more.

brada4 · August 9, 2024, 9:24am

in short authentication is mandatory.

shailesh1 · August 9, 2024, 10:01am

Hi,
I was asking for documentation or example just to be clear on the points for SNMPv3 in openwrt.
I will explain what I tried and how it has not been successful yet.
What I treid->
I followed this link Setting Up snmpv3 before creating new query. and also How do set SNMP V3 user name and password on openwrt.
issue->
As I see /etc/snmp/snmpd.conf does not get any entry related to what I edited in /etc/init.d/snmpd and /etc/config/snmpd. That is why I was asking for any specific solution on SNMPv3 for Openwrt 19.07 and 22.03.

bmork · August 9, 2024, 10:11am

Yes, there must be a gazillion ways to make that happen. I guess you selected one of them