[dpdk-users] Packet drop when using KNI sample application

[dpdk-users] Packet drop when using KNI sample application

[Amit Sharma]

Hi,

While running the DPDK KNI sample application, we are facing packet drop
after some time.

*Setup:-*
1. 2 VMs configured using Ubuntu 14.04
2. eth0 of both VMs connected to each other, and able to ping

*DPDK related setup:-*
1. 1st VM eth0 is bound with DPDK driver[bind=uio_pci_generic]
2. Insert the KNI module in Linux kernel[insmod rte_kni.ko].
3. Start the KNI application [*./build/kni -c 0x3 -n 4 -- -P -p 0x1
--config="(0,0,1)"*].
4. Assign the ip address to vEth0 [*ifconfig vEth0 10.0.1.2*]
5. start the tcpdump on vEth0
6. From 2nd VM try to ping 8.8.8.8

*Issue:- *
ping works fine for around 400-500 packets(we reserved 2000 2MB hugepages).
after that ping packet is never sent back to VM2
on further investigation we found *rte_eth_tx_burst *always returns 0 when
the problem occurs
we are investigating it further, But before that any help is welcome


on the side note, we have another issue with log levels, to investigate the
above issue we were trying to enable the logs for PMD
using the following code

rte_set_log_type(RTE_LOGTYPE_PMD, 1);

rte_set_log_level(RTE_LOG_DEBUG);

during initialization we see some logs from PMD, But after that no logs
during receive and transmission of packets, any idea why is that?

Thanks
Amit Sharma

Re: [dpdk-users] Packet drop when using KNI sample application

[Andriy Berestovskyy]

Hey Amit,
Regarding the pings. Try to set the same MAC on vEth as you have on
eth0 prior the unbind, i.e.:

# ifconfig vEth hw ether <eth0 MAC>


Regarding the logs. There are compile-time options to enable debugs in
PMDs. Please see config/common_base file for the complete list.

Not sure which driver you use, but for virtio-net you could try to
enable *_VIRTIO_DEBUG_RX/TX and then recompile the DPDK and the KNI
example.

Regards,
Andriy

On Mon, Sep 19, 2016 at 9:59 AM, Amit Sharma <amit.sh1094@gmail.com> wrote:
> Hi,
>
> While running the DPDK KNI sample application, we are facing packet drop
> after some time.
>
> *Setup:-*
> 1. 2 VMs configured using Ubuntu 14.04
> 2. eth0 of both VMs connected to each other, and able to ping
>
> *DPDK related setup:-*
> 1. 1st VM eth0 is bound with DPDK driver[bind=uio_pci_generic]
> 2. Insert the KNI module in Linux kernel[insmod rte_kni.ko].
> 3. Start the KNI application [*./build/kni -c 0x3 -n 4 -- -P -p 0x1
> --config="(0,0,1)"*].
> 4. Assign the ip address to vEth0 [*ifconfig vEth0 10.0.1.2*]
> 5. start the tcpdump on vEth0
> 6. From 2nd VM try to ping 8.8.8.8
>
> *Issue:- *
> ping works fine for around 400-500 packets(we reserved 2000 2MB hugepages).
> after that ping packet is never sent back to VM2
> on further investigation we found *rte_eth_tx_burst *always returns 0 when
> the problem occurs
> we are investigating it further, But before that any help is welcome
>
>
> on the side note, we have another issue with log levels, to investigate the
> above issue we were trying to enable the logs for PMD
> using the following code
>
> rte_set_log_type(RTE_LOGTYPE_PMD, 1);
>
> rte_set_log_level(RTE_LOG_DEBUG);
>
> during initialization we see some logs from PMD, But after that no logs
> during receive and transmission of packets, any idea why is that?
>
> Thanks
> Amit Sharma



-- 
Andriy Berestovskyy

Re: [dpdk-users] Packet drop when using KNI sample application

[Amit Sharma]

Hi Andiry,

We already changed the vEth0 mac address [same as eth0 mac address].

For reproducing the issue, please follow below mention steps:-
1. Assign the ip address to vEth0.
2. take the port down [*ifconfig vEth0 down*]
3. up the port [*ifconfig vEth0 up*]
4. wait for 400-500 ping Packet, issue is going to reproduce.

PS:- when we do port down and up, once port is up. Issue will occur.

Br
Amit Sharma

On Thu, Sep 22, 2016 at 1:37 PM, Andriy Berestovskyy <aber@semihalf.com>
wrote:

> Hey Amit,
> Regarding the pings. Try to set the same MAC on vEth as you have on
> eth0 prior the unbind, i.e.:
>
> # ifconfig vEth hw ether <eth0 MAC>
>
>
> Regarding the logs. There are compile-time options to enable debugs in
> PMDs. Please see config/common_base file for the complete list.
>
> Not sure which driver you use, but for virtio-net you could try to
> enable *_VIRTIO_DEBUG_RX/TX and then recompile the DPDK and the KNI
> example.
>
> Regards,
> Andriy
>
> On Mon, Sep 19, 2016 at 9:59 AM, Amit Sharma <amit.sh1094@gmail.com>
> wrote:
> > Hi,
> >
> > While running the DPDK KNI sample application, we are facing packet drop
> > after some time.
> >
> > *Setup:-*
> > 1. 2 VMs configured using Ubuntu 14.04
> > 2. eth0 of both VMs connected to each other, and able to ping
> >
> > *DPDK related setup:-*
> > 1. 1st VM eth0 is bound with DPDK driver[bind=uio_pci_generic]
> > 2. Insert the KNI module in Linux kernel[insmod rte_kni.ko].
> > 3. Start the KNI application [*./build/kni -c 0x3 -n 4 -- -P -p 0x1
> > --config="(0,0,1)"*].
> > 4. Assign the ip address to vEth0 [*ifconfig vEth0 10.0.1.2*]
> > 5. start the tcpdump on vEth0
> > 6. From 2nd VM try to ping 8.8.8.8
> >
> > *Issue:- *
> > ping works fine for around 400-500 packets(we reserved 2000 2MB
> hugepages).
> > after that ping packet is never sent back to VM2
> > on further investigation we found *rte_eth_tx_burst *always returns 0
> when
> > the problem occurs
> > we are investigating it further, But before that any help is welcome
> >
> >
> > on the side note, we have another issue with log levels, to investigate
> the
> > above issue we were trying to enable the logs for PMD
> > using the following code
> >
> > rte_set_log_type(RTE_LOGTYPE_PMD, 1);
> >
> > rte_set_log_level(RTE_LOG_DEBUG);
> >
> > during initialization we see some logs from PMD, But after that no logs
> > during receive and transmission of packets, any idea why is that?
> >
> > Thanks
> > Amit Sharma
>
>
>
> --
> Andriy Berestovskyy
>