0

We have an Ubuntu Server 16.04.7 virtual machine running on top of Proxmox 6.3.

On reboot of the host, this machine comes up with an "empty" /etc/resolv.conf:

# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
#     DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN

If I subsequently reboot this virtual machine, /etc/resolv.conf gets populated as expected:

# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
#     DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN
nameserver 192.168.100.10
nameserver 192.168.100.11
search domain.com

/etc/network/interfaces is as follows:

auto lo
iface lo inet loopback

auto ens18
iface ens18 inet static
    address 192.168.100.189
    netmask 255.255.255.0
    network 192.168.100.0
    broadcast 192.168.100.255
    gateway 192.168.100.1
    # dns-* options are implemented by the resolvconf package, if installed
    dns-nameservers 192.168.100.10 192.168.100.11
    dns-search domain.com

resolvconf is installed, and I can't find any meaningful differences between this installation and any of the many other virtual machines we have. The contents of /etc/resolvconf on this machine are identical to another working machine on the same node; we haven't edited the resolv.conf.d files.

We are also running keepalived on this node, with configuration as follows:

vrrp_instance VI_1 {
    state BACKUP
    interface ens18
    virtual_router_id 188
    priority 150
    advert_int 1
    notify /script/to/start/and/stop/fetchmail
    virtual_ipaddress {
        192.168.100.188
    }
}

where /script/to/start/and/stop/fetchmail is basically as it says: a script to start and stop fetchmail depending on whether or not this node is the master.

Where do I even begin to start looking to resolve (pun intentional!) this problem?

3
  • Just checking - have you edited your resolv.conf.d files? Also - I assume this is an ubuntu server machine?
    – Pizza
    Dec 1, 2020 at 8:00
  • No DHCP. Yes, Ubuntu Server. resolv.conf.d unmodified versus another working machine on the same node. Dec 1, 2020 at 8:51
  • 1
    I ended up removing the resolvconf package (and along with it the ubuntu-minimal metapackage) and creating a static /etc/resolv.conf file. We never upgrade our server OSes anyway -- we install a new and copy across the data so we have a rollback possibility when upgrading -- so the removal of the metapackage is a non-issue for us. Dec 1, 2020 at 11:18

0

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.