Customer might rely on the behavior that directly modify /etc/hosts and /etc/resolv.conf, can be persistent across reboot.
From 7.0 U3 on, content of /etc/hosts and /etc/resolv.conf are moved to configstore. They are no longer sticky bit file.
Direct update using text editor will not be Persistent across reboot. User should use public cli or API to update them.
For /etc/hosts, following is supported:
esxcli network ip hosts list
esxcli network ip hosts add
esxcli network ip hosts list remove
For /etc/resolv.conf, following is supported:
esxcli network ip dns
From 7.0 U3 on, content of /etc/hosts and /etc/resolv.conf are moved to configstore.
There is no workaround available.