Dear Maintainers, I am new to the reporting process for iproute2 thus please bear with me.
I am playing around with ERSPAN version 2 and noticed a valueless key on the JSON output for iproute2. When creating an ERSPAN interface using the following command: $ ip link add dev myerspan type erspan seq key 30 local 192.168.1.4 \ remote 192.168.1.1 erspan_ver 2 erspan_dir ingres The interface is created - as expected - and also the information can be read back in "human readable" format by: $ ip -d link show myerspan 211: myerspan@NONE: <BROADCAST,MULTICAST> mtu 1460 qdisc noop state DOWN mode DEFAULT group default qlen 1000 link/ether b6:e5:28:78:fa:54 brd ff:ff:ff:ff:ff:ff promiscuity 0 minmtu 68 maxmtu 0 erspan remote 192.168.1.1 local 192.168.1.4 ttl inherit ikey 0.0.0.30 okey 0.0.0.30 iseq oseq erspan_ver 2 erspan_dir ingress erspan_hwid 0 addrgenmode none numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 This proper lists the key/value pair of "erspan_dir ingress". When now switching to JSON output mode, the "erspan_dir" key won't have a value. Output has been stripped to only contain the relevant keys in this structure: $ ip -d -j link show myerspan [{... "erspan_ver":2,"erspan_dir":"erspan_hwid":"0" ... }] Both erspan_ver and erspan_hwid are populated with the proper values, but erspan_dir is a valueless key which will break most JSON parses (e.g. the one from Python) I have tested this with the following iproute2 versions: iproute2-5.11.0 iproute2-5.9.0 If you can point me to the location which could be responsible for this issue, I am happy to submit a fix to the net tree. Thanks in advance, Christian Poessinger