[pve-devel] [PATCH] add routed network mode

[Alexandre DERUMIER]

>>Maybe we can manually add the entry with 'arp -s ..' - should that work? 

I don't known, seem that something is related to linux routing not working with tap devices with proxy arp.


client  -----------------> proxmox host---------------->guest tap
------ 
10.0.0.2                 10.0.0.1                      192.168.1.1



client : route add 192.168.1.1 gw 10.0.0.1

proxmox host :  arp -n : 192.168.1.1 ether   da:fb:56:76:36:1b   C                     tap
echo 0 > /proc/sys/net/ipv4/conf/tap/proxy_arp


from client :
traceroute to 192.168.1.1 (192.168.1.1), 30 hops max, 60 byte packets
 1  kvmtest1.odiso.net (10.0.0.1)  0.156 ms  0.144 ms  0.133 ms
 2  * * *
 3  * * *
 4  * * *



then 

echo 1 > /proc/sys/net/ipv4/conf/tap/proxy_arp

traceroute to 192.168.1.1 (192.168.1.1), 30 hops max, 60 byte packets
 1  kvmtest1.odiso.net (10.0.0.1)  0.167 ms  0.152 ms  0.139 ms
 2  192.168.1.2 (192.168.1.1)  0.412 ms  0.402 ms  0.388 ms


then 
echo 0 > /proc/sys/net/ipv4/conf/tap/proxy_arp

traceroute to 192.168.1.1 (192.168.1.1), 30 hops max, 60 byte packets
 1  kvmtest1.odiso.net (10.0.0.1)  0.167 ms  0.152 ms  0.139 ms
 2  192.168.1.2 (192.168.1.1)  0.412 ms  0.402 ms  0.388 ms

?????????????????? working for some seconds ??????????

 then try again

traceroute to 192.168.1.1 (192.168.1.1), 30 hops max, 60 byte packets
 1  kvmtest1.odiso.net (10.0.0.1)  0.156 ms  0.144 ms  0.133 ms
 2  * * *
 3  * * *
 4  * * *



But in any case, the packet can reach the proxmox host, so it's something in proxmox host routing.

(In any case, client only have proxmox host mac-ip in his arp table and proxmox host have tap mac-ip in his arp table too)




----- Mail original ----- 

De: "Dietmar Maurer" <dietmar at proxmox.com> 
À: "Dietmar Maurer" <dietmar at proxmox.com>, "Alexandre DERUMIER" <aderumier at odiso.com> 
Cc: pve-devel at pve.proxmox.com 
Envoyé: Lundi 26 Août 2013 17:47:34 
Objet: RE: [PATCH] add routed network mode 

> > So we need to use proxy-arp, to get macaddress of host instead tap 
> > interface. 
> > 
> > Do you really need proxy-arp on $external_iface ? 
> 
> I though both is needed - but I will retest tomorrow. 

Maybe we can manually add the entry with 'arp -s ..' - should that work?