What I've done:
1, modify the /etc/ssh/ssh_config as
Ciphers aes128-cbc,3des-cbc
2, Use another user huawei to test
2.1 ssh huawei
@Mdu OK
2.2 ansible mdu -m ping -vvv, will hang forever unless ctrl-c to interupt
root@ansible:~# ansible mdu -m ping -vvv
ansible 2.5.1
config file = /etc/ansible/ansible.cfg
configured module search path = [u'/root/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
ansible python module location = /usr/lib/python2.7/dist-packages/ansible
executable location = /usr/bin/ansible
python version = 2.7.15+ (default, Oct 7 2019, 17:39:04) [GCC 7.4.0]
Using /etc/ansible/ansible.cfg as config file
Parsed /etc/ansible/hosts inventory source with ini plugin
META: ran handlers
Using module file /usr/lib/python2.7/dist-packages/ansible/modules/system/ping.py
<10.11.104.2> ESTABLISH SSH CONNECTION FOR USER: huawei
<10.11.104.2> SSH: EXEC sshpass -d12 ssh -C -o ControlMaster=auto -o ControlPersist=60s -o StrictHostKeyChecking=no -o User=huawei -o ConnectTimeout=10 -o ControlPath=/root/.ansible/cp/9850d987fb 10.11.104.2 '/bin/sh -c '"'"'echo ~ && sleep 0'"'"''
*My host file:
[mdu]
ma5626 ansible_ssh_host=10.11.104.2 ansible_ssh_user=huawei ansible_ssh_pass=ESPL888espl