Some news about the problem...
after receiving some indirect Matej suggestions from Mahdavian, I've
looked into the checksum problem mentioned here:
http://wiki.xensource.com/xenwiki/XenFaq#head-4ce9767df34fe1c9cf4f85f7e07cb10110eae9b7
This time I've tried to connect to an http service on a phisical lan
host (telnet 192.168.99.202 80) from the testing DomU (10.0.0.102)
here are the results of tcpdump -nvv on the various elements of the lan
connected bridge in Dom0 during the connection tests (192.168.99.88 is
the fw 'external' IP correctly set by SNAT rule) :
ON vif1.1 - DomU side of bridge :
tcpdump -nvvi vif1.1
tcpdump: WARNING: vif1.1: no IPv4 address assigned
tcpdump: listening on vif1.1, link-type EN10MB (Ethernet), capture size
96 bytes
17:31:07.423789 ARP, Ethernet (len 6), IPv4 (len 4), Request who-has
192.168.99.202 tell 192.168.99.88, length 28
17:31:07.423889 ARP, Ethernet (len 6), IPv4 (len 4), Reply
192.168.99.202 is-at 00:09:6b:89:d0:8a, length 46
17:31:07.423911 IP (tos 0x10, ttl 63, id 3345, offset 0, flags [DF],
proto TCP (6), length 60)
192.168.99.88.56168 > 192.168.99.202.80: Flags [S], cksum 0x8d22
(correct), seq 244003632, win 5840, options [mss 1460,sackOK,TS val
474657 ecr 0,nop,wscale 5], length 0
....
here the cksum field is correct
ON br1 - the bridge itself:
tcpdump -nvvi br1
tcpdump: listening on br1, link-type EN10MB (Ethernet), capture size 96
bytes
17:38:13.454259 IP (tos 0x10, ttl 63, id 40899, offset 0, flags [DF],
proto TCP (6), length 60)
192.168.99.88.54824 > 192.168.99.202.80: Flags [S], cksum 0x5545
(correct), seq 2632204777, win 5840, options [mss 1460,sackOK,TS val
581162 ecr 0,nop,wscale 5], length 0
again the cksum field is correct
ON peth0 - the phisical NIC :
tcpdump -nvvi peth0 port not 22
tcpdump: WARNING: peth0: no IPv4 address assigned
tcpdump: listening on peth0, link-type EN10MB (Ethernet), capture size
96 bytes
17:40:48.397392 IP (tos 0x10, ttl 63, id 59382, offset 0, flags [DF],
proto TCP (6), length 60)
192.168.99.88.44172 > 192.168.99.202.80: Flags [S], cksum 0x48a2
(incorrect -> 0x05a8), seq 774410895, win 5840, options [mss
1460,sackOK,TS val 619897 ecr 0,nop,wscale 5], length 0
Here the cksum field is INCORRECT thus the packet is probably refused !
I've tried to switch off all forms of offloading from peth0 and also
from eth0 and eth1 in fw DomU (ethtool -K peth0 tx off rx off sg off tso
off ufo off gso off) but the result is the same !
I'm also still confused about the reason why icmp packets (pings) don't
even show up on vif1.1 while tcp connection tries do... any ideas ?
What next ? Do I need to try a completely new xenified kernel ?
Many thanks in advance to all...
Sauro.
On 08/09/2010 14:25, Sauro Saltini wrote:
On 08/09/2010 10:42, Fajar A. Nugraha wrote:
On Wed, Sep 8, 2010 at 4:18 AM, Sauro Saltini<saltini@xxxxxx> wrote:
My current configuration is :
- Xen 4.0.0
- DOM0 kernel 2.6.31.13
- DOMU kernels either 2.6.31.13 or 2.6.36-rc3 (vanilla)
As soon as I've converted the fw DomU's to a PV domain (using either
2.6.31.13 or 2.6.36-rc3 kernels with PV drivers) something changed in a
weird way...
Do you mean convert it to PV domain, or keep it as HVM but use PV
drivers?
I've converted it to a PV domain (builder=linux)
on Dom0 "tcpdump -nvvi br0" (br0 = external bridge) never shows up any
traffic !
What does tcpdump on domU's vif (by default it's named vifx.y, where x
and are numbers) within dom0 shows?
Does both dom0 and your PV domU has ip forwarding
(/proc/sys/net/ipv4/ip_forward) enabled?
Do you still use ioemu line? What does your domU config look like?
tcpdump on domU's vif shows no traffic, except some arp requests
coming from the firewall domU asking for the external pinged address.
Both dom0 and domU has ip_forward activated
I have type=paravirtual for both firewall domU's nics in domU's config
my config is quite simple:
kernel='/boot/vmlinuz-r410-2.6.31.13'
builder='linux'
memory=512
name='fw'
vcpus=1
vif=[ 'type=paravirtual, bridge=br0, mac=00:16:3e:00:00:02',
'type=paravirtual, bridge=br1, mac=00:16:3e:00:00:20' ]
disk=[ 'drbd:fw,hda,w' ]
on_poweroff='destroy'
on_reboot='restart'
on_crash='restart'
boot='c'
root='/dev/xvda3 ro'
sdl=0
vnc=0
The chosen kernel is the same xenified kernel built from sources and
used for dom0
Please help...
Many thanks in advance.
It seems that the packet flow interrupts in some way inside xen's PV
netfront/netback drivers (i.e. between vethx.y and vifx.y) but ONLY
for packets coming from another domU and forwarded.
As I said i can regularly ping both domU's network and external lan
from the fw domU, only the packets coming from the other domU's
disappear !
Just for clarity, having :
testing (pinger) domU : 10.0.0.102 /24 (gw 10.0.0.101)
fw domU "internal" nic -eth0- (domU's gateway): 10.0.0.101 /24
fw domU "external" nic -eth1- (bridged to LAN): 192.168.99.88 /24
pinged lan host : 192.168.99.202 /24
On fw domU:
echo "1" > /proc/sys/net/ipv4/ip_forward
iptables -t nat -A POSTROUTING -o eth1 -j MASQUERADE
Pinging 192.168.99.202 from FW works, and tcpdump -nvvi on dom0 (both
listening on vifx.y or bridge) gives:
...
14:09:40.553104 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto
ICMP (1), length 84)
192.168.99.88 > 192.168.99.202: ICMP echo request, id 24837, seq
1, length 64
14:09:40.553223 IP (tos 0x0, ttl 64, id 21099, offset 0, flags [none],
proto ICMP (1), length 84)
192.168.99.202 > 192.168.99.88: ICMP echo reply, id 24837, seq 1,
length 64
...
Pinging 192.168.99.202 from testing domU (10.0.0.102) doesn't work,
and tcpdump -nvvi on dom0 (both listening on vifx.y or bridge) gives
(every 5 to 10 seconds):
....
14:17:29.922210 ARP, Ethernet (len 6), IPv4 (len 4), Request who-has
192.168.99.202 tell 192.168.99.88, length 28
14:17:29.922304 ARP, Ethernet (len 6), IPv4 (len 4), Reply
192.168.99.202 is-at 00:09:6b:89:d0:8a, length 46
....
but no icmp traffic at all !
You can try using xenified kernel on domU and see if it helps: patch
from http://code.google.com/p/gentoo-xen-kernel/downloads/list +
kernel 2.6.34.6 (or whatever 2.6.34.x that the patch can cleanly apply
to).
_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users
_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users
|
Home