DNSMasq ignores a client on SDN simple zone

JimP

New Member
Jan 13, 2024
12
1
3
I have set a simple SND zone and a network in it: 10.20.20.0/24.

Code:
dhcp-option=tag:myZone-10.20.20.0-24,option:router,10.20.20.1
dhcp-range=set:myZone-10.20.20.0-24,10.20.20.0,static,255.255.255.0,infinite
log-dhcp
interface=myZone

Two clients out of three in in the zone do receive DHCP lease. this is for Ubuntu with desktop:

Code:
feb 03 07:55:28 dv dnsmasq-dhcp[917158]: 444172515 available DHCP subnet: 10.20.20.0/255.255.255.0
feb 03 07:55:28 dv dnsmasq-dhcp[917158]: 444172515 client provides name: lu
feb 03 07:55:28 dv dnsmasq-dhcp[917158]: 444172515 DHCPREQUEST(myNet) 10.20.20.103 bc:24:11:43:e3:42
feb 03 07:55:28 dv dnsmasq-dhcp[917158]: 444172515 tags: myNet-10.20.20.0-24, known, myNet
feb 03 07:55:28 dv dnsmasq-dhcp[917158]: 444172515 DHCPACK(myNet) 10.20.20.103 bc:24:11:43:e3:42 lu
feb 03 07:55:28 dv dnsmasq-dhcp[917158]: 444172515 requested options: 1:netmask, 2:time-offset, 6:dns-server, 12:hostname,

One client out of three does not receive DHCP lease, Ubuntu without desktop:

Code:
feb 03 07:55:43 dv dnsmasq-dhcp[917158]: 3819140195 client provides name: dev
feb 03 07:55:43 dv dnsmasq-dhcp[917158]: 3819140195 DHCPDISCOVER(hackNet) bc:24:11:8d:7a:4c ignored

What do I do so the client receives a DHCP lease?
 
What is the output of the following command? Oftentimes it can help resutarting the client, since it regenerates and reloads the dnsmasq configuration. Hot reload with running VMs is sometimes a bit tricky due to we have to reload the ethers file for dnsmasq.

Code:
cat /etc/dnsmasq.d/<zone_name>/ethers
 
  • Like
Reactions: JimP
What is the output of the following command? Oftentimes it can help resutarting the client, since it regenerates and reloads the dnsmasq configuration. Hot reload with running VMs is sometimes a bit tricky due to we have to reload the ethers file for dnsmasq.

Code:
cat /etc/dnsmasq.d/<zone_name>/ethers
Yep, `ethers` lacks this VM. But why?
Multiple `dnsmasq` and VM restarting do not result in adding the host to the `ethers`.
 
Is there an entry for the VM in the IPAM? How does the VM configuration look like?
 
After rebooting Proxmox host the problem VM is added to ethers and works. May be some bug is involved.

Before reboot there WAS a lease in IPAM, but not in ethers.

In problematic VM I have also used manual `dhclient ens18` lease obtaining. `dnsmasq` ignored requests (because of no entry in `ethers`).
 
Last edited: