CentOS + MS Bot Framework: Solving error "ChatConnector: receive - invalid token"

When I deploy my chat bot written with MS Bot Framework on CentOS, I got the error "ERROR: ChatConnector: receive - invalid token. Check bot's app ID & Password", although I provide exactly my bot's app ID & Password.

After googling, I know the problem is server time not corrected (in my case, it is late ~ 20 minutes), so the security token is invalid.

You can solve this easily by syncing your server time with a standard NTP (Network Time Protocol) server. Below are steps.

1. Install ntp and ntpdate

# yum install ntp ntpdate

2. Enable ntpd service

# systemctl start ntpd
# systemctl enable ntpd

Check its status:

# systemctl status ntpd

3. Add some CentOS NTP servers

# ntpdate -u -s 0.centos.pool.ntp.org 1.centos.pool.ntp.org 2.centos.pool.ntp.org

4. Restart ntpd service

# systemctl restart ntpd

5. Check again

# timedatectl
# date

Addition, let set hardware clock to the current server time:

# hwclock  -w

Now you can start your bot without this error. Cheers!