Dslite.sh: add_protocol: not found

Using a Archer C7 with the optimized snapshot on a DS--Lite line i found this in the log, one per second at day and night. The throughput is lowered to 1/3 and ping above 150ms since these errors in syslog.

Sat Jun  2 12:07:19 2018 daemon.notice netifd: Interface 'WAN' is setting up now
Sat Jun  2 12:07:20 2018 daemon.notice netifd: WAN (15265): Command failed: Unknown error
Sat Jun  2 12:07:20 2018 daemon.notice netifd: Interface 'WAN' is now down
Sat Jun  2 12:07:20 2018 daemon.notice netifd: Interface 'WAN' is setting up now
Sat Jun  2 12:07:21 2018 daemon.info odhcpd[1468]: Using a RA lifetime of 1800 seconds on br-lan
Sat Jun  2 12:07:21 2018 daemon.notice netifd: WAN (15354): Command failed: Unknown error
Sat Jun  2 12:07:21 2018 daemon.notice netifd: Interface 'WAN' is now down
Sat Jun  2 12:07:21 2018 daemon.notice netifd: Interface 'WAN' is setting up now

So i got the idea to fire up the related script 'dslite.sh' by hand and got this.

root@scylla:/lib/netifd/proto# sh ./dslite.sh
./dslite.sh: line 102: add_protocol: not found

root@scylla:/lib/netifd/proto# opkg install ds-lite
Package ds-lite (7-2) installed in root is up to date.

As the package is installed, what produce the error here?

LEDE Reboot SNAPSHOT r5264-94491a1571 / LuCI Master (git-17.309.31241-676ce11)

The netifd scripts aren't "stand-alone" scripts but are intended to be run in the context that netifd creates, including several sh functions that are required.

Yes there is some kind of problem behind that, so i filed a bug report about that.

Hello,did you find a solution ?

Since problems with the ds-lite module are the same with version 19 i did a final cut. My router is configured as dual-stack, so i use a wan4 and wan6 device instead of the ds-lite. This also fixed the horrible VPN problems through ds-lite.