mac address changes consistently.

jimknock3445

New Member
Nov 3, 2020
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I'm seeing my connection to my management web console get interrupted a lot. I've noticed that on my gateway, which is a pfsense box the IP address changes mac address a lot in the logs.

Nov 3 07:26:20 kernel arp: 192.168.3.9 moved from d4:ae:52:71:61:61 to d4:ae:52:71:61:59 on em2
Nov 3 07:26:15 kernel arp: 192.168.3.9 moved from d4:ae:52:71:61:59 to d4:ae:52:71:61:61 on em2

Why is this happening and how do I stop this?
 

Stoiko Ivanov

Proxmox Staff Member
Staff member
May 2, 2018
5,879
802
148
2 guesses:
* you have a duplicate IP (2 devices have the same ip-address configured)
* you have setup a bond-mode, which is not supported by your switches

* which devices have the 2 mac-addresses: d4:ae:52:71:61:59 and d4:ae:52:71:61:61 (on linux you can see that with `ip link show` on bsd (pfsense) ifconfig ?
* post your network configuration (/etc/network/interfaces)

I hope this helps!
 

jimknock3445

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Nov 3, 2020
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These IPs are handed out via dhcp staticatly. There shouldn't been two device with the same IP. The mac address ending in 61 doesn't appear, t

ip link show
2: eno1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master vmbr0 state UP mode DEFAULT group default qlen 1000
link/ether d4:ae:52:71:61:59 brd ff:ff:ff:ff:ff:ff

root@dc:~# ip neigh
192.168.3.1 dev vmbr0 lladdr 00:15:17:c6:8b:e4 REACHABLE
root@dc:~#

root@dc:~# ip link show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eno1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master vmbr0 state UP mode DEFAULT group default qlen 1000
link/ether d4:ae:52:71:61:59 brd ff:ff:ff:ff:ff:ff
3: eno2: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether d4:ae:52:71:61:5b brd ff:ff:ff:ff:ff:ff
4: eno3: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether d4:ae:52:71:61:5d brd ff:ff:ff:ff:ff:ff
5: eno4: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether d4:ae:52:71:61:5f brd ff:ff:ff:ff:ff:ff
6: ovs-system: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether 82:10:6f:3a:c6:9b brd ff:ff:ff:ff:ff:ff
7: vmbr2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/ether 6e:4f:55:01:d3:43 brd ff:ff:ff:ff:ff:ff
8: vmbr0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000
link/ether d4:ae:52:71:61:59 brd ff:ff:ff:ff:ff:ff
9: vmbr1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/ether 1a:e6:44:12:36:eb brd ff:ff:ff:ff:ff:ff
58: tap103i0: <BROADCAST,MULTICAST,PROMISC,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master fwbr103i0 state UNKNOWN mode DEFAULT group default qlen 1000
link/ether 76:49:15:07:03:32 brd ff:ff:ff:ff:ff:ff
59: fwbr103i0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000
link/ether ae:c6:19:4c:c1:22 brd ff:ff:ff:ff:ff:ff
60: fwpr103p0@fwln103i0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master vmbr0 state UP mode DEFAULT group default qlen 1000
link/ether 32:4d:d8:b4:eb:dd brd ff:ff:ff:ff:ff:ff
61: fwln103i0@fwpr103p0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master fwbr103i0 state UP mode DEFAULT group default qlen 1000
link/ether ae:c6:19:4c:c1:22 brd ff:ff:ff:ff:ff:ff
62: tap100i0: <BROADCAST,MULTICAST,PROMISC,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master fwbr100i0 state UNKNOWN mode DEFAULT group default qlen 1000
link/ether ee:54:8d:c5:04:06 brd ff:ff:ff:ff:ff:ff
63: fwbr100i0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000
link/ether 6a:dc:bf:30:3d:ee brd ff:ff:ff:ff:ff:ff
64: fwpr100p0@fwln100i0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master vmbr0 state UP mode DEFAULT group default qlen 1000
link/ether ea:d4:66:5f:e4:32 brd ff:ff:ff:ff:ff:ff
65: fwln100i0@fwpr100p0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master fwbr100i0 state UP mode DEFAULT group default qlen 1000
link/ether 6a:dc:bf:30:3d:ee brd ff:ff:ff:ff:ff:ff


configuration of the interface
--- /etc/network/interfaces 2020-10-27 13:45:02.387345999 -0500
+++ /etc/network/interfaces.new 2020-11-02 14:47:38.692047313 -0600
@@ -28,13 +28,3 @@
bridge-stp off
bridge-fd 0

-auto vmbr1
-iface vmbr1 inet manual
- bridge-ports none
- bridge-stp off
- bridge-fd 0
-
-allow-ovs vmbr2
-iface vmbr2 inet manual
- ovs_type OVSBridge
-
 

Stoiko Ivanov

Proxmox Staff Member
Staff member
May 2, 2018
5,879
802
148
These IPs are handed out via dhcp staticatly. There shouldn't been two device with the same IP.
PVE needs a statically configured IP. - maybe that's the reason: the PVE host has 192.168.3.9 configured statically, while the DHCP server hands it out to some other device.

The mac address ending in 61 doesn't appear,
maybe it exists on another physical host connected to the same network?

also please post the complete content of /etc/network/interfaces (not the diff between the current config an the one that will get applied upon next reboot

finally - consider using regular linux-bridges instead of OVS - it's simpler and should be able to handle network configuration in most scenarios.

https://pve.proxmox.com/pve-docs/pve-admin-guide.html#sysadmin_network_configuration
 

jimknock3445

New Member
Nov 3, 2020
3
0
1
30
PVE needs a statically configured IP. - maybe that's the reason: the PVE host has 192.168.3.9 configured statically, while the DHCP server hands it out to some other device.


maybe it exists on another physical host connected to the same network?

also please post the complete content of /etc/network/interfaces (not the diff between the current config an the one that will get applied upon next reboot

finally - consider using regular linux-bridges instead of OVS - it's simpler and should be able to handle network configuration in most scenarios.

https://pve.proxmox.com/pve-docs/pve-admin-guide.html#sysadmin_network_configuration
Even if an IP was static, why is the mac address changing? IP addressing isn't really an issue when I must refresh my arp cache consistently.
 
Last edited:

vapour

New Member
Sep 28, 2020
14
0
1
I'm experiencing the same problem and have read a number of post regarding the same. Unfortunately, no staff member, from what I've seen, has been able to answer this question. What I'm experiencing is terrible speed, the MAC address changes every nth of a second, and now I'm seeing LAN traffic in the DMZ and vise-versa in my Pfsense logs. The 2 MAC addresses map to both my LAN and DMZ.



ip link show output
Note: (Bold MAC addresses are the ones that the PVE host flip-flop between)

ip link show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eno1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master vmbr0 state UP mode DEFAULT group default qlen 1000
link/ether 78:2b:cb:5e:94:4f brd ff:ff:ff:ff:ff:ff
altname enp1s0f0
3: eno2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master vmbr2 state UP mode DEFAULT group default qlen 1000
link/ether 78:2b:cb:5e:94:51 brd ff:ff:ff:ff:ff:ff
altname enp1s0f1
4: eno3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master vmbr3 state UP mode DEFAULT group default qlen 1000
link/ether 78:2b:cb:5e:94:53 brd ff:ff:ff:ff:ff:ff
altname enp2s0f0
5: eno4: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master vmbr4 state UP mode DEFAULT group default qlen 1000
link/ether 78:2b:cb:5e:94:55 brd ff:ff:ff:ff:ff:ff
altname enp2s0f1
7: vmbr3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000
link/ether 78:2b:cb:5e:94:53 brd ff:ff:ff:ff:ff:ff
8: vmbr0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000
link/ether 78:2b:cb:5e:94:4f brd ff:ff:ff:ff:ff:ff
9: vmbr2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000
link/ether 78:2b:cb:5e:94:51 brd ff:ff:ff:ff:ff:ff
10: vmbr4: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000
link/ether 78:2b:cb:5e:94:55 brd ff:ff:ff:ff:ff:ff
11: tap100i0: <BROADCAST,MULTICAST,PROMISC,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master vmbr4 state UNKNOWN mode DEFAULT group default qlen 1000
link/ether aa:77:6f:58:f0:54 brd ff:ff:ff:ff:ff:ff
12: tap100i1: <BROADCAST,MULTICAST,PROMISC,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master vmbr3 state UNKNOWN mode DEFAULT group default qlen 1000
link/ether e2:ca:6d:ab:39:8d brd ff:ff:ff:ff:ff:ff
13: tap100i2: <BROADCAST,MULTICAST,PROMISC,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master vmbr2 state UNKNOWN mode DEFAULT group default qlen 1000
link/ether ba:77:96:2c:76:49 brd ff:ff:ff:ff:ff:ff
14: veth105i0@if2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master vmbr3 state UP mode DEFAULT group default qlen 1000
link/ether fe:4c:2e:73:62:bb brd ff:ff:ff:ff:ff:ff link-netnsid 0

ip neigh output;
Note: (vmbr0 --> PVE Host, vmbr2 --> DMZ, 192...1 --> PFsense, 192...254 --> Management laptop)

192.168.1.1 dev vmbr2 lladdr ce:6f:cc:2a:c3:a0 STALE
192.168.1.1 dev vmbr0 lladdr ce:6f:cc:2a:c3:a0 REACHABLE
192.168.1.254 dev vmbr0 lladdr 10:0b:a9:08:8b:98 REACHABLE
192.168.1.254 dev vmbr2 lladdr 10:0b:a9:08:8b:98 STALE
fe80::c81e:52ff:fe38:af95 dev vmbr2 lladdr ca:1e:52:38:af:95 STALE
fe80::14e6:48ff:fef7:402c dev vmbr2 lladdr 16:e6:48:f7:40:2c STALE
fe80::401a:a90e:79f:a326 dev vmbr2 lladdr 90:70:65:d0:8e:ae STALE
fe80::7a2b:cbff:fe5e:9453 dev vmbr0 lladdr 78:2b:cb:5e:94:53 STALE
fe80::ac86:32ff:feed:3958 dev vmbr2 lladdr ae:86:32:ed:39:58 STALE
fe80::8c79:3ff:fe8d:5584 dev vmbr2 lladdr 8e:79:03:8d:55:84 STALE
fe80::7a4b:87ff:fe46:47e dev vmbr2 lladdr 78:4b:87:46:04:7e STALE
fe80::9417:3dff:fe66:5e61 dev vmbr2 lladdr 96:17:3d:66:5e:61 STALE
fe80::7a2b:cbff:fe5e:9453 dev vmbr2 lladdr 78:2b:cb:5e:94:53 STALE
fe80::120b:a9ff:fe08:8b98 dev vmbr2 lladdr 10:0b:a9:08:8b:98 STALE
fe80::217:10ff:fe90:c58f dev vmbr4 lladdr 00:17:10:90:c5:8f router STALE
fe80::a53f:c321:eefd:647c dev vmbr2 lladdr 10:98:c3:c3:8b:c2 STALE

Thanks in advance for any help

V
 

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