PYNQ-2.7 on ZCU104 has network connection problem

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1

This is my first post.
I download the PYNQ-v2.7 image file for ZCU104, and could successfully boot the system with the ZCU104 board.
I found out that network connection to outer world failed with the names, such as, google.com. I checked with PYNQ v2.6, and it works with this version.
It seems to me that name resolving seems not working in v2.7.

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2

Can you provide more info?
How is your board connected to your network?

Did you run ip addr on the board?
Did you check your network?

Cathal

3

Dear Cathal,

My ZCU104 board is connected to a local network using a cabe through a hub The local network in an office shared by several devices is connected to outer world through a conventional gateway, which I think is a sort of typical network environment.
The board has two IP addr, the given one 192.168.2.99, and another provate address dynamically allocated by DHCP.
With the v2.6, I could access github.com to set up DPU-PYNQ without any problem, but no success with v2.7 because of network access failure. I used the brand-new images for both versions, with the same ZCU104 board, while keeping the network environment.

Let me know if you need more information.
I would hope to hear some good news soon.
Thanks in advance.

Hideki

4

Another information.
Behavior for ping is different between PYNQ v2.6 and v2.7.
In PYNQ v2.7, I can ping from ZCU104 some local machines, such as my MacBook and Ubuntu desktop machine;

ping AAAA.local
ping BBBB.local
and also ping ZCU104 from these machines,
% ping pynq.local
In the PYNQ v2.6, these were not possible.

Hideki

5

Did you run ip addr on the board? Can you copy the output here?

Cathal

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6

Dear Cathal,

xilinx@pynq:~$ ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: dummy0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN group default qlen 1000
link/ether a6:31:1c:44:aa:2b brd ff:ff:ff:ff:ff:ff
3: sit0@NONE: mtu 1480 qdisc noop state DOWN group default qlen 1000
link/sit 0.0.0.0 brd 0.0.0.0
4: can0: <NOARP,ECHO> mtu 16 qdisc noop state DOWN group default qlen 10
link/can
5: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
link/ether 00:0a:35:07:1e:0c brd ff:ff:ff:ff:ff:ff
inet 192.168.2.127/24 brd 192.168.2.255 scope global dynamic eth0
valid_lft 13328sec preferred_lft 13328sec
inet 192.168.2.99/24 brd 192.168.2.255 scope global secondary eth0:1
valid_lft forever preferred_lft forever
inet6 2408:211:4e23:4c00:20a:35ff:fe07:1e0c/64 scope global dynamic mngtmpaddr
valid_lft 14326sec preferred_lft 12526sec
inet6 fe80::20a:35ff:fe07:1e0c/64 scope link
valid_lft forever preferred_lft forever

xilinx@pynq:~$ ping github.com
ping: github.com: Temporary failure in name resolution

xilinx@pynq:~$ ping 13.114.40.48
PING 13.114.40.48 (13.114.40.48) 56(84) bytes of data.
64 bytes from 13.114.40.48: icmp_seq=1 ttl=42 time=11.1 ms
64 bytes from 13.114.40.48: icmp_seq=2 ttl=42 time=8.36 ms
64 bytes from 13.114.40.48: icmp_seq=3 ttl=42 time=6.74 ms
64 bytes from 13.114.40.48: icmp_seq=4 ttl=42 time=7.40 ms
^C
— 13.114.40.48 ping statistics —
4 packets transmitted, 4 received, 0% packet loss, time 3004ms
rtt min/avg/max/mdev = 6.737/8.385/11.053/1.644 ms

Hideki

7

try adding the line nameserver 8.8.8.8 to the the /etc/resolv.conf file:
nano /ete/resolv.conf → nameserver 8.8.8.8
This one has worked for me once.

8

/etc/resolve.conf is dynamically created, and changing it directly is not recommended.
Thus, I tried;

sudo systemd-resolve —interface=eth0 —set-dns=8.8.8.8

systemd-resolve —status
I could see DNS Server for eth0, and I now can ping to outer world.
ping github.cim
Thank you very much for your cooporation.
Best Hideki

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9

Hi guys, I have solved the problem by following steps posted on stackoverflow originally:

  1. Disable “systemd-resolved” service:
    sudo systemctl disable systemd-resolved.service

  2. Stop the service:
    sudo systemctl stop systemd-resolved.service

  3. Remove the link to “/run/systemd/resolve/stub-resolv.conf” in “/etc/resolv.conf”
    sudo rm /etc/resolv.conf

  4. Add a manually created “resolv.conf” in “/etc/”
    sudo vim /etc/resolv.conf

  5. Add your prefered DNS server there
    nameserver 8.8.8.8

This solutions work well for my own ZCU104 board, I can connect to the Internet after doing this. It still works well after every reboot.

This solution is from the following post on Stackoverflow: ubuntu - ping: google.com: Temporary failure in name resolution - Stack Overflow

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