May be related to #927 & #1010. Ticket at ssh2-sftp-client. Version 0.8.9 of ssh2 (ssh2-sftp-client 6.0.1) takes 3 seconds after DEBUG: Parser: IN_PACKETDATAAFTER, packet: KEXDH_GEX_GROUP. Debug ...
When I type "opkg install openssh-sftp-server" I can see "package unknown". 2 days ago this operation was successful. Also, in mipc_24kc packages openssh-sftp-server was there.