On Sun, Aug 06, 2023 at 05:17:23PM +0800, Jon Smart wrote:
> It's a VPS provided by a local ISP. The VPS has a static IPv4.
> Do you know how to know if /etc/resolv.conf is modified by dhcp?
The first thing you could do is check whether a DHCP client daemon
is running. That's usually a sign.
Failing that, find out what your primary network interface's name is,
and then find out how that network interface is brought up. In a server
configuration, it's *usually* brought up by a stanza in the
/etc/network/interfaces file. If that stanza consists of a line
ending with "dhcp", then voila.
If the primary network interface is not configured in /e/n/i then the
second most likely configuration is NetworkManager. Usually if NM
is in the picture, /etc/resolv.conf will be a symlink, and you will
see evidence of NM both in the symlink's target, and in the contents
of the file. Thus,
ls -ld /etc/resolv.conf
cat /etc/resolv.conf
Both of these should give you hints, if NM is involved.
