dpctl error connecting to switch - pox

I'm going through openflow tutorial
https://github.com/CPqD/ofsoftswitch13/wiki/OpenFlow-1.3-Tutorial
when I try to execute
$dpctl dump-flows tcp:127.0.0.1:6634
or
$dpctl show tcp:127.0.0.1:6634
I'm always getting the same error
dpctl: Error connecting to switch show. (Address family not supported by protocol)
so can you please tell me why I'm getting this error?
Thanks in advance.

My mistake. I was creating the topology in Mininet specifying the controller as remote
sudo mn --mac --controller remote,ip=127.0.0.1
without running the controller on the machine first, so I just ran the controller first(NOX in my case)
cd nox/build/src
./nox_core -v -i ptcp:6633 switch
and that solved the problem.
thanks

Related

Busybox wget strange behaviour

I need some help with a really strange problem.
I use wget (busybox) to obtain the the IP address of some remote clients, to use it on a DNS (a sort of "homemade ddns"). Those clients run a script that every 5 mins calls
wget -O /dev/null "https://my_dns.org/poll.php?user=User_N&pwd=password_N"
Everything was fine, until I updated my http server to remove TLS1.0/TLS1.1
After updating: running the above command on the clients' console it still works OK, while running it automatically (launching it from a script in /etc/init.d) I get this error:
Connecting to my_dns.org (www.xxx.yyy.zzz:443)
wget: error getting response: Connection reset by peer
...Any idea about why does this happen, and how to fix...?
(The shell on the clients runs as root...)
Thank you in advance for your help
Regards

Error when opening pgAdmin 4 on mac

I have installed version 4-1.5, but when opening it, it always shows this error "The application server could not be contacted."
I removed the local directory hidden and resolved:
$ cd ~
$ rm -r .pgadmin/
Note: macOS Sierra (10.12.6) and pgAdmin 4-1.6. Also you are going to loose configuration data like database list tree, et al.
The Databases will remain intact since you are modifying/deleting PgAdmin related data not any of Postgresql itself.
I had the same issue, I fixed it by stopping the service in Postgres app, then start pgAdmin, and then start the Postgres service. I was able to connect it after that. Hope this help.
I had same error, but in my case I use wrong port number for the database
On my system Safari is the problem as it was default browser.
To fix, make Chrome your default browser and try relaunching pgadmin4
OR
Manually fix by
$ cat ~/.pgAdmin4.5704814747986328352.addr
http://127.0.0.1:62631/?key=0ec25e6a-dfe2-483e-9814-b315ea87c3cf
Paste what you get in Chrome

Device not configured after sshfs attempt

After using sshfs on my Mac I am no longer able to see my user directory.
When I open a terminal window I see the following:
Last login: Mon May 22 10:54:30 on ttys003
mkdir: /Users/<username>/.bash_sessions: Device not configured
-bash: /Users/<username>/.bash_profile: Device not configured
touch: /Users/<username>/.bash_sessions/35166655-583B-47CC-9BCF-5E785DD5E46E.historynew: Device not configured
Is there any way to fix this?
Cheers
Paul
I used to use sshfs and got this error; the only way to fix it I found without rebooting was:
sudo diskutil umount force /path/to/mount
I've recently been trying https://github.com/spion/adbfs-rootless for something else and find I can get into the same situation, the "fix" works in that case as well.
Wasn't getting anywhere so took a chance and did a reboot. Everything seems to be OK now.

rsync: failed to connect to hgdownload.cse.ucsc.edu (128.114.119.163)

For reasons I don't understand, rsync does not work for me since today.
I tried to fix the problem by following steps described here : https://askubuntu.com/questions/628102/15-04-rsync-connection-refused
but it did not work...
I am working on a laptop with Ubuntu 16.04 as OS, and have a wired ethernet connection.
I made several queries on the UCSC server yesterday, so maybe their server blocks my connection ?
Example of a query I would like to do :
rsync -a -P rsync://hgdownload.cse.ucsc.edu/goldenPath/hg38/database/cytoBand.txt.gz ./
Here is the Error message :
rsync: failed to connect to hgdownload.cse.ucsc.edu (128.114.119.163): Connection refused (111)
rsync error: error in socket IO (code 10) at clientserver.c(128) [Receiver=3.1.1]
Tell me what you think and if there is any solution to make it work again.
Thank you in advance for your help.
Edit:
UCSC answered me : no problem on their side. The problem definitely come from me. Still looking for a solution.
It looks like the rsync daemon is not running on the remote host, or perhaps it is running on a non-standard port (default is 873).
It's also possible that connections are being blocked by a firewall. Were your earlier successful connections made from the same location, or are you now testing from elsewhere?
As a workaround you can access the files via HTTP using any browser or HTTP command line tools such as curl, wget et. al. Either of these should work:
$ curl http://hgdownload.cse.ucsc.edu/goldenPath/hg38/database/cytoBand.txt.gz -o cytoBand.txt.gz
$ wget http://hgdownload.cse.ucsc.edu/goldenPath/hg38/database/cytoBand.txt.gz
Since rsync is still not working (I tweet to UCSC to ask about it),
I decided to use the tools curl and wget that mhawke advised me, but using the ftp adresses instead of http (slower) :
curl ftp://hgdownload.cse.ucsc.edu/goldenPath/hg38/database/cytoBand.txt.gz -o cytoBand.txt.gz
wget http://hgdownload.cse.ucsc.edu/goldenPath/hg38/database/cytoBand.txt.gz
If anyone has a solution for the rsync problem, or any informations saying that the problem could come from the UCSC server, I would be thankful.
Cheers !
Edit:
I received an answer from UCSC : no problem about rsync on the side of the UCSC server. So the problem definitely comes from me. I tried on 3 different computers on different places, all running under Ubuntu 16.04. I am still looking for a solution.
Thanks to a mail answer from a guy working at UCSC:
I tried the same command line but on the mirror site : ftp://hgdownload-sd.cse.ucsc.edu.
which gave this command line :
rsync -a -P rsync://hgdownload-sd.cse.ucsc.edu/goldenPath/hg38/database/cytoBand.txt.gz ./
I tried it. It worked.
And here comes the best part: in my case I try the command line that did not work... and it works again:
rsync -a -P rsync://hgdownload.cse.ucsc.edu/goldenPath/hg38/database/cytoBand.txt.gz ./
So I did not had any explanations on where does the problem came from. But problem solved!

boot2docker shellinit command ended up in error "Error requesting socket: exit status 255"

Installed boot2docker on OSX, as per instructions of http://boot2docker.io/. After that started the application. In a terminal, boot2docker shellinit command started and ended up in throwing this error "Error requesting socket: exit status 255". Tried boot2docker stop--->delete--->download--->init--->up . It didn't help. The version I used is v1.3.1. Any ideas why it might have failed? Thanks!
Finally this solution worked for me. It seems like, it is mandatory to have the localhost assigned to 127.0.0.1 in our hosts file(location is /etc/hosts). The following line should be there in /etc/hosts
127.0.0.1 localhost
And do the following. At the end, assign variables as the console shows.
boot2docker init
boot2docker download
boot2docker up
try to see the actual error in virtualbox screen.
For me it was because visualization was not enabled in my bios.
I could see “this kernel requires an x86-64 CPU, but only detects an i686 CPU, unable to boot” error in virtual box screen
in bios, security>visualization>enable>save and exit
Good luck