Package: dnsmasq
Version: 2.75-1
Severity: normal
Please forgive my vague title. It is a bug that has been hitting me for
some time, but since I had a work around, I never reported it. But doing
now. I hope I can explain it.
rrs@learner:/media/SSHD/rrs-home/devel/config_validator (master)$ cat
/etc/network/interfaces.d/lxcbr0.conf
# This bridge will is used to NAT LXC containers' traffic
auto lxcbr0
iface lxcbr0 inet static
#bridge_stp off
address 172.16.10.1
netmask 255.255.0.0
#up ip link set dev lxcbr0 up
#down ip link set dev lxcbr0 down
pre-up brctl addbr lxcbr0
post-down brctl delbr lxcbr0
post-down echo 0 > /proc/sys/net/ipv4/ip_forward
post-down echo 0 > /proc/sys/net/ipv6/conf/all/forwarding
post-up echo 1 > /proc/sys/net/ipv4/ip_forward
post-up echo 1 > /proc/sys/net/ipv6/conf/all/forwarding
#post-up iptables -A POSTROUTING -t nat -s 172.16.10.1/16 -j MASQUERADE
#pre-down iptables -D POSTROUTING -t nat -s 172.16.10.1/16 -j MASQUERADE
#post-up iptables -A FORWARD -i lxcbr0 -s 172.16.10.1/16 -j ACCEPT
#pre-down iptables -D FORWARD -i lxcbr0 -s 172.16.10.1/16 -j ACCEPT
# add checksum so that dhclient does not complain.
# udp packets staying on the same host never have a checksum filled else
post-up iptables -A POSTROUTING -t mangle -p udp --dport bootpc -s
172.16.0.0/16 -j CHECKSUM --checksum-fill
pre-down iptables -D POSTROUTING -t mangle -p udp --dport bootpc -s
172.16.0.0/16 -j CHECKSUM --checksum-fill
2015-09-14 / 22:35:20 ♒♒♒ ☺
This is what my bridge interface is. I like it this way, because I can
instrcut both, Containers and Virtual Machines, to bind to this bridge,
and then I can focus on all my management on this interface. And all the
VMs and Containers get to talk to each other on the bridge.
I use dnsmasq to serve the DHCP requests. My settings are as defined
below:
rrs@learner:/media/SSHD/rrs-home/devel/config_validator (master)$ cat
/etc/dnsmasq.d/50myLXC
# Bind it to the LXC interface
interface=lxcbr0
bind-interfaces
# Want DHCP client FQDN
#dhcp-fqdn
# Domain name and ip range with lease time
domain=lxc.local,172.16.10.0/16
#dhcp-range=192.168.122.100,192.168.122.200,1h
dhcp-range=lxcbr0,172.16.10.10,172.16.10.200,1h
# DHCP options
dhcp-option=40,lxc.local
log-dhcp
2015-09-14 / 22:37:49 ♒♒♒ ☺
The name got stuck because I started with configuring it for containers,
but I use the same setup for the VMs. In VirtualBox, for each Guest VM,
I choose "Bridged Adapter" as the setting.
The problem:
I use my laptopt as usual. Multiple suspends/resumes. And then I just
fire up a Guest VM. And it timesout in getting a DHCP address.
In the logs, it shows that the DHCP address was offered.
Sep 14 22:18:54 learner dnsmasq-dhcp[1407]: 1240112453 next server: 172.16.10.1
Sep 14 22:18:54 learner dnsmasq-dhcp[1407]: 1240112453 broadcast response
Sep 14 22:18:54 learner dnsmasq-dhcp[1407]: 1240112453 sent size: 1 option: 53
message-type 2
Sep 14 22:18:54 learner dnsmasq-dhcp[1407]: 1240112453 sent size: 4 option: 54
server-identifier 172.16.10.1
Sep 14 22:18:54 learner dnsmasq-dhcp[1407]: 1240112453 sent size: 4 option: 51
lease-time 1h
Sep 14 22:18:54 learner dnsmasq-dhcp[1407]: 1240112453 sent size: 4 option: 58
T1 30m
Sep 14 22:18:54 learner dnsmasq-dhcp[1407]: 1240112453 sent size: 4 option: 59
T2 52m30s
Sep 14 22:18:54 learner dnsmasq-dhcp[1407]: 1240112453 sent size: 4 option: 1
netmask 255.255.0.0
Sep 14 22:18:54 learner dnsmasq-dhcp[1407]: 1240112453 sent size: 4 option: 28
broadcast 172.16.255.255
Sep 14 22:18:54 learner dnsmasq-dhcp[1407]: 1240112453 sent size: 4 option: 3
router 172.16.10.1
Sep 14 22:18:54 learner dnsmasq-dhcp[1407]: 1240112453 sent size: 4 option: 6
dns-server 172.16.10.1
Sep 14 22:18:54 learner dnsmasq-dhcp[1407]: 1240112453 sent size: 9 option: 15
domain-name lxc.local
Sep 14 22:18:57 learner dnsmasq-dhcp[1407]: 1240112453 available DHCP range:
172.16.10.10 -- 172.16.10.200
Sep 14 22:18:57 learner dnsmasq-dhcp[1407]: 1240112453 client provides name:
debian
Sep 14 22:18:57 learner dnsmasq-dhcp[1407]: 1240112453 DHCPDISCOVER(lxcbr0)
172.16.10.77 08:00:27:ec:39:96
Sep 14 22:18:57 learner dnsmasq-dhcp[1407]: 1240112453 tags: lxcbr0
Sep 14 22:18:57 learner dnsmasq-dhcp[1407]: 1240112453 DHCPOFFER(lxcbr0)
172.16.10.77 08:00:27:ec:39:96
Sep 14 22:18:57 learner dnsmasq-dhcp[1407]: 1240112453 requested options:
1:netmask, 28:broadcast, 2:time-offset, 3:router,
Sep 14 22:18:57 learner dnsmasq-dhcp[1407]: 1240112453 requested options:
15:domain-name, 6:dns-server, 119:domain-search,
Sep 14 22:18:57 learner dnsmasq-dhcp[1407]: 1240112453 requested options:
12:hostname, 44:netbios-ns, 47:netbios-scope,
Sep 14 22:18:57 learner dnsmasq-dhcp[1407]: 1240112453 requested options:
26:mtu, 121:classless-static-route, 42:ntp-server
Sep 14 22:18:57 learner dnsmasq-dhcp[1407]: 1240112453 next server: 172.16.10.1
Sep 14 22:18:57 learner dnsmasq-dhcp[1407]: 1240112453 broadcast response
Sep 14 22:18:57 learner dnsmasq-dhcp[1407]: 1240112453 sent size: 1 option: 53
message-type 2
Sep 14 22:18:57 learner dnsmasq-dhcp[1407]: 1240112453 sent size: 4 option: 54
server-identifier 172.16.10.1
Sep 14 22:18:57 learner dnsmasq-dhcp[1407]: 1240112453 sent size: 4 option: 51
lease-time 1h
Sep 14 22:18:57 learner dnsmasq-dhcp[1407]: 1240112453 sent size: 4 option: 58
T1 30m
Sep 14 22:18:57 learner dnsmasq-dhcp[1407]: 1240112453 sent size: 4 option: 59
T2 52m30s
Sep 14 22:18:57 learner dnsmasq-dhcp[1407]: 1240112453 sent size: 4 option: 1
netmask 255.255.0.0
Sep 14 22:18:57 learner dnsmasq-dhcp[1407]: 1240112453 sent size: 4 option: 28
broadcast 172.16.255.255
Sep 14 22:18:57 learner dnsmasq-dhcp[1407]: 1240112453 sent size: 4 option: 3
router 172.16.10.1
Sep 14 22:18:57 learner dnsmasq-dhcp[1407]: 1240112453 sent size: 4 option: 6
dns-server 172.16.10.1
Sep 14 22:18:57 learner dnsmasq-dhcp[1407]: 1240112453 sent size: 9 option: 15
domain-name lxc.local
Sep 14 22:19:01 learner dnsmasq-dhcp[1407]: 1240112453 available DHCP range:
172.16.10.10 -- 172.16.10.200
Sep 14 22:19:01 learner dnsmasq-dhcp[1407]: 1240112453 client provides name:
debian
Sep 14 22:19:01 learner dnsmasq-dhcp[1407]: 1240112453 DHCPDISCOVER(lxcbr0)
172.16.10.77 08:00:27:ec:39:96
Sep 14 22:19:01 learner dnsmasq-dhcp[1407]: 1240112453 tags: lxcbr0
Sep 14 22:19:01 learner dnsmasq-dhcp[1407]: 1240112453 DHCPOFFER(lxcbr0)
172.16.10.77 08:00:27:ec:39:96
Sep 14 22:19:01 learner dnsmasq-dhcp[1407]: 1240112453 requested options:
1:netmask, 28:broadcast, 2:time-offset, 3:router,
Sep 14 22:19:01 learner dnsmasq-dhcp[1407]: 1240112453 requested options:
15:domain-name, 6:dns-server, 119:domain-search,
Sep 14 22:19:01 learner dnsmasq-dhcp[1407]: 1240112453 requested options:
12:hostname, 44:netbios-ns, 47:netbios-scope,
Sep 14 22:19:01 learner dnsmasq-dhcp[1407]: 1240112453 requested options:
26:mtu, 121:classless-static-route, 42:ntp-server
Sep 14 22:19:01 learner dnsmasq-dhcp[1407]: 1240112453 next server: 172.16.10.1
Sep 14 22:19:01 learner dnsmasq-dhcp[1407]: 1240112453 broadcast response
But the client times out waiting for the IP address.
Then I just restarted the dnsmasq service:
Sep 14 22:29:03 learner systemd[1]: Stopping dnsmasq - A lightweight DHCP and
caching DNS server...
Sep 14 22:29:03 learner dnsmasq[1407]: no servers found in
/var/run/dnsmasq/resolv.conf, will retry
Sep 14 22:29:05 learner systemd[1]: Stopped dnsmasq - A lightweight DHCP and
caching DNS server.
Sep 14 22:29:05 learner systemd[1]: Starting dnsmasq - A lightweight DHCP and
caching DNS server...
Sep 14 22:29:05 learner dnsmasq[1547]: dnsmasq: syntax check OK.
Sep 14 22:29:05 learner dnsmasq[1556]: started, version 2.75 cachesize 150
Sep 14 22:29:05 learner dnsmasq[1556]: compile time options: IPv6 GNU-getopt
DBus i18n IDN DHCP DHCPv6 no-Lua TFTP conntrack ipset auth DNSSEC loop-detect
inotify
Sep 14 22:29:05 learner dnsmasq-dhcp[1556]: DHCP, IP range 172.16.10.10 --
172.16.10.200, lease time 1h
Sep 14 22:29:05 learner dnsmasq-dhcp[1556]: DHCP, sockets bound exclusively to
interface lxcbr0
Sep 14 22:29:05 learner dnsmasq[1556]: no servers found in
/var/run/dnsmasq/resolv.conf, will retry
Sep 14 22:29:05 learner dnsmasq[1556]: read /etc/hosts - 10 addresses
Sep 14 22:29:05 learner dnsmasq[1556]: reading /var/run/dnsmasq/resolv.conf
Sep 14 22:29:05 learner dnsmasq[1556]: using nameserver 192.168.1.1#53
Sep 14 22:29:11 learner systemd[1]: Started dnsmasq - A lightweight DHCP and
caching DNS server.
And now, when I boot the Guest VMs, they do get the IP. Logs below:
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 available DHCP range:
172.16.10.10 -- 172.16.10.200
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 client provides name:
debian
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 DHCPDISCOVER(lxcbr0)
172.16.10.40 08:00:27:5a:d8:7a
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 tags: lxcbr0
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 DHCPOFFER(lxcbr0)
172.16.10.40 08:00:27:5a:d8:7a
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 requested options:
1:netmask, 28:broadcast, 2:time-offset, 3:router,
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 requested options:
15:domain-name, 6:dns-server, 119:domain-search,
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 requested options:
12:hostname, 44:netbios-ns, 47:netbios-scope,
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 requested options:
26:mtu, 121:classless-static-route, 42:ntp-server
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 next server: 172.16.10.1
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 sent size: 1 option: 53
message-type 2
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 sent size: 4 option: 54
server-identifier 172.16.10.1
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 sent size: 4 option: 51
lease-time 1h
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 sent size: 4 option: 58
T1 30m
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 sent size: 4 option: 59
T2 52m30s
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 sent size: 4 option: 1
netmask 255.255.0.0
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 sent size: 4 option: 28
broadcast 172.16.255.255
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 sent size: 4 option: 3
router 172.16.10.1
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 sent size: 4 option: 6
dns-server 172.16.10.1
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 sent size: 9 option: 15
domain-name lxc.local
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 available DHCP range:
172.16.10.10 -- 172.16.10.200
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 client provides name:
debian
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 DHCPREQUEST(lxcbr0)
172.16.10.40 08:00:27:5a:d8:7a
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 tags: lxcbr0
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 DHCPACK(lxcbr0)
172.16.10.40 08:00:27:5a:d8:7a debian
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 requested options:
1:netmask, 28:broadcast, 2:time-offset, 3:router,
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 requested options:
15:domain-name, 6:dns-server, 119:domain-search,
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 requested options:
12:hostname, 44:netbios-ns, 47:netbios-scope,
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 requested options:
26:mtu, 121:classless-static-route, 42:ntp-server
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 next server: 172.16.10.1
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 sent size: 1 option: 53
message-type 5
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 sent size: 4 option: 54
server-identifier 172.16.10.1
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 sent size: 4 option: 51
lease-time 1h
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 sent size: 4 option: 58
T1 30m
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 sent size: 4 option: 59
T2 52m30s
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 sent size: 4 option: 1
netmask 255.255.0.0
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 sent size: 4 option: 28
broadcast 172.16.255.255
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 sent size: 4 option: 3
router 172.16.10.1
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 sent size: 4 option: 6
dns-server 172.16.10.1
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 sent size: 9 option: 15
domain-name lxc.local
Sep 14 22:30:07 learner dnsmasq-dhcp[1556]: 3774021946 sent size: 6 option: 12
hostname debian
And this one for the BSD VM.
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 client provides name:
debian-bsd
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 DHCPDISCOVER(lxcbr0)
172.16.10.108 08:00:27:46:31:d7
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 tags: lxcbr0
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 DHCPOFFER(lxcbr0)
172.16.10.108 08:00:27:46:31:d7
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 requested options:
1:netmask, 28:broadcast, 2:time-offset, 3:router,
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 requested options:
15:domain-name, 6:dns-server, 119:domain-search,
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 requested options:
12:hostname, 44:netbios-ns, 47:netbios-scope,
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 requested options:
26:mtu, 121:classless-static-route, 42:ntp-server
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 next server: 172.16.10.1
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 sent size: 1 option: 53
message-type 2
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 sent size: 4 option: 54
server-identifier 172.16.10.1
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 sent size: 4 option: 51
lease-time 1h
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 sent size: 4 option: 58
T1 30m
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 sent size: 4 option: 59
T2 52m30s
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 sent size: 4 option: 1
netmask 255.255.0.0
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 sent size: 4 option: 28
broadcast 172.16.255.255
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 sent size: 4 option: 3
router 172.16.10.1
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 sent size: 4 option: 6
dns-server 172.16.10.1
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 sent size: 9 option: 15
domain-name lxc.local
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 available DHCP range:
172.16.10.10 -- 172.16.10.200
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 client provides name:
debian-bsd
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 DHCPREQUEST(lxcbr0)
172.16.10.108 08:00:27:46:31:d7
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 tags: lxcbr0
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 DHCPACK(lxcbr0)
172.16.10.108 08:00:27:46:31:d7 debian-bsd
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 requested options:
1:netmask, 28:broadcast, 2:time-offset, 3:router,
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 requested options:
15:domain-name, 6:dns-server, 119:domain-search,
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 requested options:
12:hostname, 44:netbios-ns, 47:netbios-scope,
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 requested options:
26:mtu, 121:classless-static-route, 42:ntp-server
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 next server: 172.16.10.1
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 sent size: 1 option: 53
message-type 5
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 sent size: 4 option: 54
server-identifier 172.16.10.1
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 sent size: 4 option: 51
lease-time 1h
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 sent size: 4 option: 58
T1 30m
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 sent size: 4 option: 59
T2 52m30s
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 sent size: 4 option: 1
netmask 255.255.0.0
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 sent size: 4 option: 28
broadcast 172.16.255.255
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 sent size: 4 option: 3
router 172.16.10.1
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 sent size: 4 option: 6
dns-server 172.16.10.1
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 sent size: 9 option: 15
domain-name lxc.local
Sep 14 22:30:58 learner dnsmasq-dhcp[1556]: 2713556075 sent size: 10 option: 12
hostname debian-bsd
So, this is how I concluded to file it against dnsmasq.
And, thank you for dnsmasq. It is one of the most useful and important
tool in my daily life.
-- System Information:
Debian Release: stretch/sid
APT prefers testing
APT policy: (990, 'testing'), (500, 'unstable'), (101, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386
Kernel: Linux 4.2.0+ (SMP w/4 CPU cores)
Locale: LANG=en_IN.utf8, LC_CTYPE=en_IN.utf8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
Versions of packages dnsmasq depends on:
ii dnsmasq-base 2.75-1
ii init-system-helpers 1.23
ii netbase 5.3
dnsmasq recommends no packages.
Versions of packages dnsmasq suggests:
ii resolvconf 1.78
-- no debconf information
