What is the exact value of the IPv6 address you are trying to configure?
You can easily test manual configuration of IPv6 addresses via the CLI as follows:
1) Configure Node 1:
> panid 0x1234
Done
> ifconfig up
Done
> thread start
Done
2) Configure Node 2:
> panid 0x1234
Done
> ifconfig up
Done
> thread start
Done
3) List IPv6 addresses on Node 2:
> ipaddr
fdde:ad00:beef:0:0:ff:fe00:5801
fdde:ad00:beef:0:ea5e:6210:c6e0:931e
fe80:0:0:0:8c75:b363:87dd:3f67
Done
4) Configure new mesh-local IPv6 address on Node 2 and verify:
> ipaddr add fdde:ad00:beef:0::beef
Done
> ipaddr
fdde:ad00:beef:0:0:0:0:beef
fdde:ad00:beef:0:0:ff:fe00:4400
fdde:ad00:beef:0:ea5e:6210:c6e0:931e
fe80:0:0:0:8c75:b363:87dd:3f67
Done
5) Ping manually configured address from Node 1.
> ping fdde:ad00:beef:0:0:0:0:beef
8 bytes from fdde:ad00:beef:0:0:0:0:beef: icmp_seq=1 hlim=64 time=10ms
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Jonathan Hui