unsupported DSA tag: qca

[ErwanMAS]

Hi ,
What we need todo to solve this error ?

root@OpenWrt:~# tcpdump -nei eth1
tcpdump: unsupported DSA tag: qca

root@OpenWrt:~# tcpdump --version
tcpdump version 4.99.5
libpcap version 1.10.5 (with TPACKET_V3)
32-bit build, 64-bit time_t

[infrastation]

What does tcpdump -L -i eth1 print?

[ErwanMAS]

same error

root@OpenWrt:~#  tcpdump -L -i eth1
tcpdump: unsupported DSA tag: qca

[infrastation]

It seems you have hardware that uses the QCA tagging for DSA, which the Linux kernel supports (seemingly since 2015), but libpcap does not.

[infrastation]

Which specific hardware is this, and which OpenWrt release?

[ErwanMAS]

Which specific hardware is this, and which OpenWrt release?

so i have 2 dsa tag that are no supported qca / mtk

Linksys EA7500 V1

cat /etc/openwrt_release ; cat /etc/board.json | jq .model ; tcpdump -nei eth0
DISTRIB_ID='OpenWrt'
DISTRIB_RELEASE='24.10.0-rc2'
DISTRIB_REVISION='r28161-ea17e958b9'
DISTRIB_TARGET='ipq806x/generic'
DISTRIB_ARCH='arm_cortex-a15_neon-vfpv4'
DISTRIB_DESCRIPTION='OpenWrt 24.10.0-rc2 r28161-ea17e958b9'
DISTRIB_TAINTS=''
{
  "id": "linksys,ea7500-v1",
  "name": "Linksys EA7500 V1 WiFi Router"
}
tcpdump: unsupported DSA tag: qca

Linksys EA7500 V2

cat /etc/openwrt_release ; cat /etc/board.json | jq .model ; tcpdump -nei eth0
DISTRIB_ID='OpenWrt'
DISTRIB_RELEASE='24.10.0-rc2'
DISTRIB_REVISION='r28161-ea17e958b9'
DISTRIB_TARGET='ramips/mt7621'
DISTRIB_ARCH='mipsel_24kc'
DISTRIB_DESCRIPTION='OpenWrt 24.10.0-rc2 r28161-ea17e958b9'
DISTRIB_TAINTS=''
{
  "id": "linksys,ea7500-v2",
  "name": "Linksys EA7500 v2"
}
tcpdump: unsupported DSA tag: mtk
root@ramir:~#

[0xKira]

Same problem here with OpenWrt 24.10.0-rc3

tcpdump: unsupported DSA tag: mtk

[piyushgarg]

arp-scan --localnet
pcap_activate: unsupported DSA tag: mtk

[vladimiroltean]

For the record, this is a regression, for which I've opened this pull request: #1451. Testers welcome.