[SOLVED] No ARP reply when using VLAN Linux bond with LACP

semira uthsala

Active Member
Nov 19, 2019
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Singapore
I have two severs (px1 and px2) which connect to same switch (Juniper QFX) with LACP. each server have 2 physical ports and those bonded to bond0 using LACP. I used default Linux bond (not OVS).

After create the bond I created VLAN interface on that bond like below

first server (px1)

auto bond0
iface bond0 inet manual
bond-slaves ens1f0 ens1f1
bond-miimon 100
bond-mode 802.3ad

auto bond0.40
iface bond0.40 inet static
address 192.168.40.10
netmask 24


second server (px2)

auto bond0
iface bond0 inet manual
bond-slaves ens1f0 ens1f1
bond-miimon 100
bond-mode 802.3ad

auto bond0.40
iface bond0.40 inet static
address 192.168.40.11
netmask 24

After this when I try to ping px2 to px1 I cannot ping. Then I do the tcpdump on px1 while pinging from px2.


tcpdump -nneqt -i any arp | grep 192.168.40.10
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on any, link-type LINUX_SLL (Linux cooked), capture size 262144 bytes
B 48:xxxxxxxxxxxxx vlan 40, p 0, Request who-has 192.168.40.10 tell 192.168.40.11, length 46
B 48:xxxxxxxxxxxxx vlan 40, p 0, Request who-has 192.168.40.10 tell 192.168.40.11, length 46
B 48:xxxxxxxxxxxxx vlan 40, p 0, Request who-has 192.168.40.10 tell 192.168.40.11, length 46
B 48:xxxxxxxxxxxxx vlan 40, p 0, Request who-has 192.168.40.10 tell 192.168.40.11, length 46
B 48:xxxxxxxxxxxxx vlan 40, p 0, Request who-has 192.168.40.10 tell 192.168.40.11, length 46
B 48:xxxxxxxxxxxxx vlan 40, p 0, Request who-has 192.168.40.10 tell 192.168.40.11, length 46
B 48:xxxxxxxxxxxxx vlan 40, p 0, Request who-has 192.168.40.10 tell 192.168.40.11, length 46
B 48:xxxxxxxxxxxxx vlan 40, p 0, Request who-has 192.168.40.10 tell 192.168.40.11, length 46
B 48:xxxxxxxxxxxxx vlan 40, p 0, Request who-has 192.168.40.10 tell 192.168.40.11, length 46
B 48:xxxxxxxxxxxxx vlan 40, p 0, Request who-has 192.168.40.10 tell 192.168.40.11, length 46
B 48:xxxxxxxxxxxxx vlan 40, p 0, Request who-has 192.168.40.10 tell 192.168.40.11, length 46
B 48:xxxxxxxxxxxxx vlan 40, p 0, Request who-has 192.168.40.10 tell 192.168.40.11, length 46

(I did the tcpdump on px2 while pinging from px1 and results are same)

I can see ARP request coming from server px2 but no reply to those messages from server px1.

Then I tried adding MACs manually using arp -s command on both servers and I able to ping after that.

I don't have any visibility from the switch end what are the configurations. But since both servers can see incoming ARP requests why there is no ARP reply for those messages ?

To ensure this setup working without bond, I setup 3rd physical connection to the both servers and tag vlan 50 using OVSintport. I can access the VLAN 50 and I can see both ARP request and reply coming through that connection. and I can access all the hosts on that network (192.168.50.0/24)

Proxmox v6.0


update
----------------------------
I added MTU 9000 on bond0 and bond.40 as found in some posts. But still not working.


update 2
----------------------------
When I remove one interface from bond I can reach all hosts in 192.168.40.0/24 VLAN. and ARP reply is sending properly.
 
Last edited:
Have you tried adding a bond-primary ens1f0 line to your bond config to force the use of one interface if available?
 
Hi,

Issue is due to LACP not configured properly from the switch end. After properly configure now I can access all the nodes from the bonded vlan
 
Great to hear. Can you please mark the thread as solved? Thanks :)
 
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