[nlbwmon] Unable to fetch traffic statistic data: Unexpected end of JSON input

[Louise]

Hi,
I run OpenWRT on VDK, and no traffic data is displayed.

When I checked log, I found the following error:

Sat Nov 25 18:19:02 2023 daemon.err modprobe: no module folders for kernel version 5.10.21+ found
Sat Nov 25 18:19:02 2023 daemon.notice procd: /etc/rc.d/S19firewall: mnl.c:60: Unable to initialize Netlink socket: Protocol not supported
Sat Nov 25 18:19:02 2023 daemon.err modprobe: no module folders for kernel version 5.10.21+ found
Sat Nov 25 18:19:02 2023 daemon.notice procd: /etc/rc.d/S19firewall: mnl.c:60: Unable to initialize Netlink socket: Protocol not supported
Sat Nov 25 18:19:02 2023 daemon.notice procd: /etc/rc.d/S19firewall: Unable to parse nftables JSON output: Failed to parse JSON string: unexpected end of data

Sat Nov 25 18:19:03 2023 daemon.err modprobe: no module folders for kernel version 5.10.21+ found
Sat Nov 25 18:19:03 2023 daemon.err nlbwmon[2045]: Unable to connect nfnetlink: Bad file descriptor
Sat Nov 25 18:19:03 2023 kern.info kernel: [   11.214573] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
Sat Nov 25 18:19:03 2023 daemon.notice netifd: Network device 'eth0' link is up
Sat Nov 25 18:19:03 2023 kern.info kernel: [   11.234764] ftgmac030 39000000.gmac eth0: Link is Up - 1Gbps/Full - flow control off
Sat Nov 25 18:19:03 2023 daemon.err modprobe: no module folders for kernel version 5.10.21+ found
Sat Nov 25 18:19:03 2023 daemon.err nlbwmon[2210]: Unable to connect nfnetlink: Bad file descriptor
Sat Nov 25 18:19:03 2023 user.notice nlbwmon: Reloading nlbwmon due to ifup of loopback (lo)

Then I checked the 5.10.21+ path and found that it did not exist.
However, there is a folder named 5.10.201, which contains the required kernel modules.

root@OpenWrt:/# uname -r
5.10.21+
root@OpenWrt:/# 
root@OpenWrt:/# cd /lib/modules
root@OpenWrt:/lib/modules# ls
5.10.201
root@OpenWrt:/lib/modules# 
root@OpenWrt:/lib/modules# cd 5.10.201
root@OpenWrt:/lib/modules/5.10.201# ls
crc-ccitt.ko             nf_nat.ko                nft_numgen.ko
libcrc32c.ko             nf_reject_ipv4.ko        nft_objref.ko
netlink_diag.ko          nf_reject_ipv6.ko        nft_quota.ko
nf_conntrack.ko          nf_socket_ipv4.ko        nft_redir.ko
nf_conntrack_netlink.ko  nf_socket_ipv6.ko        nlmon.ko
nf_defrag_ipv4.ko        nf_tables.ko             ppp_async.ko
nf_defrag_ipv6.ko        nfnetlink.ko             ppp_generic.ko
nf_flow_table.ko         nft_counter.ko           pppoe.ko
nf_flow_table_inet.ko    nft_ct.ko                pppox.ko
nf_flow_table_ipv4.ko    nft_flow_offload.ko      raw_diag.ko
nf_flow_table_ipv6.ko    nft_hash.ko              slhc.ko
nf_log_common.ko         nft_limit.ko             udp_diag.ko
nf_log_ipv4.ko           nft_log.ko
nf_log_ipv6.ko           nft_masq.ko

What can I do to solve this problem?
Thank you.

[frollic]

@Louise

What can I do to solve this problem?

don't run an initramfs, it's not intended for regular use.

5.10.201 is old too, your openwrt version is EOL.

[Louise]

I solved this problem using the following commands.

cd /lib/modules
ln -s 5.10.201 5.10.21+
/etc/init.d/nlbwmon start

But now, a new problem has occurred.
When I tried to look up the nlbw data, I found there was no information available.

root@OpenWrt:/# nlbw -c show
  Fam            Host (    MAC )      Layer7      Conn.   > Downld. ( > Pkts. )      Upload (   Pkts. )
root@OpenWrt:/# 

What can I do to display the information?

[frollic]

in a release from 3 years ago, we have no idea.
upgrade, like you were told last week.

[_bernd]

@Louise

VDK

Virtual Box?

[Louise]

Virtualizer Development Kit

[frollic]

It appears you are using firmware that is not from the official OpenWrt project.

When using forks/offshoots/vendor-specific builds that are "based on OpenWrt", there may be many differences compared to the official versions (hosted by OpenWrt.org). Some of these customizations may fundamentally change the way that OpenWrt works. You might need help from people with specific/specialized knowledge about the firmware you are using, so it is possible that advice you get here may not be useful.

You may find that the best options are:

1. Install an official version of OpenWrt, if your device is supported (see https://firmware-selector.openwrt.org).
2. Ask for help from the maintainer(s) or user community of the specific firmware that you are using.
3. Provide the source code for the firmware so that users on this forum can understand how your firmware works (OpenWrt forum users are volunteers, so somebody might look at the code if they have time and are interested in your issue).

If you believe that this specific issue is common to generic/official OpenWrt and/or the maintainers of your build have indicated as such, please feel free to clarify.