^_^:~/YQ601$ sudo fastboot flash recovery rec.img 
target reported max download size of 268435456 bytes
sending 'recovery' (8610 KB)...
FAILED (remote: flash tools is error)
finished. total time: 0.003s

^_^:~/YQ601$ sudo ubuntu-device-flash touch --channel=ubuntu-touch/stable/ubuntu --device mako --bootstrap
2015/11/13 18:34:59 Device is |mako|
2015/11/13 18:35:06 Flashing version 24 from ubuntu-touch/stable/ubuntu channel and server https://system-image.ubuntu.com to device mako
can't flash recovery image