[Dnsmasq-discuss] DCHP server assign from the beginning IP addresses over and over. (no icmp's)

[Ivan Pantovic]

Hi, i can't find anyone with a similar problem yet i have experienced 
quite unusual behavior of dnsmasq.

In simple words it reassigns the same IP to different MAC addresses even 
if it has them in the lease file and issues no icmp/ping requests to the 
already assigned ips.

I can see that no matter how many virtual machines i bring up, it always 
gives them one ip and can't record any icmp traffic during that time.

(tcpdump -ni eth0 icmp gives no icmp from or to the dnsmasq host)

What happens is this:

> dnsmasq-dhcp: 2515134025 available DHCP range: 192.168.99.111 -- 192.168.99.130
> dnsmasq-dhcp: 2515134025 DHCPREQUEST(eth1) 192.168.99.111 aa:8e:d8:91:48:75
> dnsmasq-dhcp: 2515134025 tags: test, known, eth1
> dnsmasq-dhcp: 2515134025 DHCPACK(eth1) 192.168.99.111 aa:8e:d8:91:48:75 vm-xxxx1-test111
> dnsmasq-dhcp: 2515134025 requested options: 1:netmask, 28:broadcast, 2:time-offset, 121:classless-static-route,
> dnsmasq-dhcp: 2515134025 requested options: 15:domain-name, 6:dns-server, 12:hostname,
> dnsmasq-dhcp: 2515134025 requested options: 40:nis-domain, 41:nis-server, 42:ntp-server,
> dnsmasq-dhcp: 2515134025 requested options: 26:mtu, 119:domain-search, 3:router
> dnsmasq-dhcp: 2515134025 next server: 192.168.99.254
> dnsmasq-dhcp: 2515134025 sent size:  1 option: 53 message-type  5
> dnsmasq-dhcp: 2515134025 sent size:  4 option: 54 server-identifier  192.168.99.254
> dnsmasq-dhcp: 2515134025 sent size:  4 option: 51 lease-time  15m
> dnsmasq-dhcp: 2515134025 sent size:  4 option: 58 T1  7m30s
> dnsmasq-dhcp: 2515134025 sent size:  4 option: 59 T2  13m4s
> dnsmasq-dhcp: 2515134025 sent size:  4 option:  1 netmask  255.255.255.0
> dnsmasq-dhcp: 2515134025 sent size:  4 option: 28 broadcast  192.168.99.255
> dnsmasq-dhcp: 2515134025 sent size:  4 option:  3 router  192.168.99.254
> dnsmasq-dhcp: 2515134025 sent size:  4 option:  6 dns-server  192.168.99.254
> dnsmasq-dhcp: 2515134025 sent size:  6 option: 15 domain-name  xxxx.com
> dnsmasq-dhcp: 2515134025 sent size: 15 option: 12 hostname  vm-xxxx1-test111
> dnsmasq-dhcp: 2515134025 available DHCP range: 192.168.99.111 -- 192.168.99.130
> dnsmasq-dhcp: 2515134025 DHCPDECLINE(eth1) 192.168.99.111 aa:8e:d8:91:48:75
> dnsmasq-dhcp: 2189493037 available DHCP range: 192.168.99.111 -- 192.168.99.130
> dnsmasq-dhcp: 2189493037 DHCPREQUEST(eth1) 192.168.99.111 9e:74:dc:32:5d:66
> dnsmasq-dhcp: 2189493037 tags: test, known, eth1
> dnsmasq-dhcp: 2189493037 DHCPACK(eth1) 192.168.99.111 9e:74:dc:32:5d:66 vm-xxxx1-test111

this are the options currently used:

> [root at vm-xxxx1-gw1 ~]# fgrep -v '#' /etc/dnsmasq.conf | sed -e '/^$/d'
> except-interface=eth0
> dhcp-sequential-ip
> dhcp-ignore-names
> domain=xxxx.com
> dhcp-host=id:tester,set:test
> dhcp-range=tag:test,192.168.99.111,192.168.99.130,15m
> dhcp-leasefile=/var/lib/misc/dnsmasq.leases
> dhcp-authoritative
> log-dhcp

> [root at vm-xxxx-gw1 ~]# uname -a
> Linux vm-xxxx-gw1 3.10.10-1-ARCH #1 SMP PREEMPT Fri Aug 30 11:30:06 CEST 2013 x86_64 GNU/Linux

the iptables are clear and the VM's and dnsmasq are on the same l2 part 
of the network.

i can't clearly see how the decision is made in source to ping or not to 
ping the address but obviously something is not working properly.

and yes my /etc/hosts file holds the names for the VM's. For the first 
VM it works great but then since the discovery of ip's in use is not 
working properly (and it might be something else since it also ignores 
the own leases file) it continue to assign the same first or second 
address (i didn't get further then that).