I ran tcpdump this morning wide open (when I ran it for port 67 and port 68
there was zero traffic detected when starting the lxc container nsa2).
When I ran tcpdump wide open I got the following traffic detected when the
lxc container starts. I again tried turning off firewalld completely and
this is still what I get as shown below. Wondering what is going on here?
[ubuntu@f33sv1 ~]$ sudo tcpdump -i lxcbr0 -vvv
dropped privs to tcpdump
tcpdump: listening on lxcbr0, link-type EN10MB (Ethernet), capture size
262144 bytes
08:34:39.305449 IP (tos 0xc0, ttl 1, id 0, offset 0, flags [DF], proto IGMP
(2), length 40, options (RA))
f33sv1 > igmp.mcast.net: igmp v3 report, 1 group record(s) [gaddr
224.0.0.252 to_ex { }]
08:34:39.305469 IP6 (hlim 1, next-header Options (0) payload length: 76)
f33sv1 > ff02::16: HBH (rtalert: 0x0000) (padn) [icmp6 sum ok] ICMP6,
multicast listener report v2, 3 group record(s) [gaddr ff02::1:3 to_ex { }]
[gaddr ff02::1:ff00:0 to_ex { }] [gaddr ff02::6a to_ex { }]
08:34:39.305542 IP6 (hlim 1, next-header Options (0) payload length: 36) ::
> ff02::16: HBH (rtalert: 0x0000) (padn) [icmp6 sum ok] ICMP6, multicast
listener report v2, 1 group record(s) [gaddr ff02::1:ff13:707c to_ex { }]
08:34:39.397672 IP6 (hlim 1, next-header Options (0) payload length: 76)
f33sv1 > ff02::16: HBH (rtalert: 0x0000) (padn) [icmp6 sum ok] ICMP6,
multicast listener report v2, 3 group record(s) [gaddr ff02::1:3 to_ex { }]
[gaddr ff02::1:ff00:0 to_ex { }] [gaddr ff02::6a to_ex { }]
08:34:39.445676 IP6 (hlim 1, next-header Options (0) payload length: 36) ::
> ff02::16: HBH (rtalert: 0x0000) (padn) [icmp6 sum ok] ICMP6, multicast
listener report v2, 1 group record(s) [gaddr ff02::1:ff13:707c to_ex { }]
08:34:39.765786 IP6 (hlim 255, next-header ICMPv6 (58) payload length: 32)
:: > ff02::1:ff13:707c: [icmp6 sum ok] ICMP6, neighbor solicitation, length
32, who has fe80::216:3eff:fe13:707c
unknown option (14), length 8 (1):
0x0000: f203 5136 6f9a
08:34:39.891089 IP6 (hlim 255, next-header ICMPv6 (58) payload length: 32)
f33sv1 > ff02::1:ff13:707c: [icmp6 sum ok] ICMP6, neighbor solicitation,
length 32, who has fe80::216:3eff:fe13:707c
source link-address option (1), length 8 (1): 00:16:3e:00:00:00
0x0000: 0016 3e00 0000
08:34:40.029649 IP (tos 0xc0, ttl 1, id 0, offset 0, flags [DF], proto IGMP
(2), length 40, options (RA))
f33sv1 > igmp.mcast.net: igmp v3 report, 1 group record(s) [gaddr
224.0.0.252 to_ex { }]
08:34:40.797778 IP6 (hlim 1, next-header Options (0) payload length: 36)
fe80::216:3eff:fe13:707c > ff02::16: HBH (rtalert: 0x0000) (padn) [icmp6
sum ok] ICMP6, multicast listener report v2, 1 group record(s) [gaddr
ff02::1:ff13:707c to_ex { }]
08:34:40.797796 IP6 (hlim 255, next-header ICMPv6 (58) payload length: 16)
fe80::216:3eff:fe13:707c > ff02::2: [icmp6 sum ok] ICMP6, router
solicitation, length 16
source link-address option (1), length 8 (1): 00:16:3e:13:70:7c
0x0000: 0016 3e13 707c
08:34:40.925732 IP6 (hlim 255, next-header ICMPv6 (58) payload length: 32)
f33sv1 > ff02::1:ff13:707c: [icmp6 sum ok] ICMP6, neighbor solicitation,
length 32, who has fe80::216:3eff:fe13:707c
source link-address option (1), length 8 (1): 00:16:3e:00:00:00
0x0000: 0016 3e00 0000
08:34:40.925787 IP6 (hlim 255, next-header ICMPv6 (58) payload length: 32)
fe80::216:3eff:fe13:707c > f33sv1: [icmp6 sum ok] ICMP6, neighbor
advertisement, length 32, tgt is fe80::216:3eff:fe13:707c, Flags
[solicited, override]
destination link-address option (2), length 8 (1): 00:16:3e:13:70:7c
0x0000: 0016 3e13 707c
08:34:40.925797 IP6 (flowlabel 0xb6a64, hlim 1, next-header TCP (6) payload
length: 44) f33sv1.60688 > fe80::216:3eff:fe13:707c.hostmon: Flags [S],
cksum 0xebef (incorrect -> 0xb854), seq 2709608773, win 64800, options [mss
1440,sackOK,TS val 789202957 ecr 0,nop,wscale 7,tfo cookiereq,nop,nop],
length 0
08:34:40.925818 IP6 (flowlabel 0xed86d, hlim 64, next-header TCP (6)
payload length: 20) fe80::216:3eff:fe13:707c.hostmon > f33sv1.60688: Flags
[R.], cksum 0xebd7 (incorrect -> 0xc74f), seq 0, ack 2709608774, win 0,
length 0
08:34:41.693783 IP6 (hlim 1, next-header Options (0) payload length: 36)
fe80::216:3eff:fe13:707c > ff02::16: HBH (rtalert: 0x0000) (padn) [icmp6
sum ok] ICMP6, multicast listener report v2, 1 group record(s) [gaddr
ff02::1:ff13:707c to_ex { }]
08:34:44.509930 IP6 (hlim 255, next-header ICMPv6 (58) payload length: 16)
fe80::216:3eff:fe13:707c > ff02::2: [icmp6 sum ok] ICMP6, router
solicitation, length 16
source link-address option (1), length 8 (1): 00:16:3e:13:70:7c
0x0000: 0016 3e13 707c
08:34:46.045831 IP6 (hlim 255, next-header ICMPv6 (58) payload length: 32)
fe80::216:3eff:fe13:707c > f33sv1: [icmp6 sum ok] ICMP6, neighbor
solicitation, length 32, who has f33sv1
source link-address option (1), length 8 (1): 00:16:3e:13:70:7c
0x0000: 0016 3e13 707c
08:34:46.045891 IP6 (hlim 255, next-header ICMPv6 (58) payload length: 24)
f33sv1 > fe80::216:3eff:fe13:707c: [icmp6 sum ok] ICMP6, neighbor
advertisement, length 24, tgt is f33sv1, Flags [solicited]
On Wed, Dec 23, 2020 at 12:14 AM Orabuntu-LXC <gilb...@orabuntu-lxc.com>
wrote:
> Hi, I cannot get dnsmasq to issue a dhcp address via lxc-net on fedora
> 33. I have compared it to a working system on Ubuntu 20.04 and what I find
> is that when an lxc container starts, there is DHCPOFFER normal activity in
> lxc-net status on Ubuntu 20.04, but not on Fedora 33 where the
> configuration is afaik exactly the same.
>
> I have tried various firewalld settings in case firewalld was blocking
> somehow, but nothing has worked including disabling firewalld entirely as
> well as disabling selinux entirely. Tomorrow I will try tcpdump and see
> if there are clues there. Thanks!
>
> --
> Gilbert Standen
> Creator Orabuntu-LXC
> 914-261-4594
> gilb...@orabuntu-lxc.com
>
>
--
Gilbert Standen
Creator Orabuntu-LXC
914-261-4594
gilb...@orabuntu-lxc.com
_______________________________________________
Dnsmasq-discuss mailing list
Dnsmasq-discuss@lists.thekelleys.org.uk
http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss
