Linode Support can help you diagnose this more if you open a ticket through your Linode Manager.
Because you mention China, there could be a chance that you're being affected by the GFW (Great Fire Wall of China).
Previously, our team has attempted to swap the IP addresses of Linodes impacted by the GFW.
With the recent developments in the GFW, our team has determined the swapping of IP addresses is ineffective in resolving the connectivity issues our customers face. The GFW will continue to block your IP address shortly after your Linode’s IP has been swapped. At this time, we are no longer swapping IP addresses for Linodes impacted by the GFW.
As we have noticed that this is mainly affecting VPN and proxy users, our recommendation for customers impacted by the GFW is to investigate different proxy and VPN options for their Linode. It’s important to understand that some users have experienced GFW filtering for specific types of proxies on their Linode. While one proxy may not work for a user, another proxy or VPN may still be accessible. If you have an existing proxy, you may want to try switching ports or use UDP. Below we’ve provided some links to common proxy and VPN software that could serve as alternatives.
*It’s important to note that some users have found that basic VPN and proxy connections (such as Shadowsocks, OpenVPN and the options provided by Streisand) are still actively filtered by the GFW. In this case, if the services above don’t work for you, you may want to consider working with some of the specialized services configured to specifically address the difficulties of the GFW.
OpenVPN with SSH tunneling -
https://www.vpnanswers.com/openvpn-over-ssh-tunnelling-tutorial-step-by-step/ (with PuTTY)
http://blog.acmelab.org/2008/07/20/mac-os-x-openvpn-bridge-ssh-tunnel-vpn-goodness/ (with Mac OSX)
https://github.com/StreisandEffect/streisand (easy setup of stunnel, tor, shadowsocks, ovpn)
ShadowsocksR - (shadowsocks with additional obfuscation making it harder to detect.)
Firefly - (A proxy software to help circumventing the Great Firewall.)
Wireguard - (a newer VPN protocol)
Another alternative users have experienced success with, is utilizing their Linode’s IPv6 address. This is located in your Linode’s Remote Access tab. While users have reported connectivity issues with their IPv4 addresses they’ve still been able to access their server via IPv6.
If you’re currently unable to connect to SSH due to the GFW, you will need to use our out of band LISH Console to make changes to your configuration:
Please note that as an unmanaged infrastructure provider we will not be able to assist you in deploying VPN and proxy services on your Linode. If you have questions about configuring these services we’d recommend reaching out to the other Linux community resources as well as our own Community Site and IRC channel: