pppd is failing for me on the Mac. I'm trying to connect to a serial port to an embedded device running lwIP. It works from both Ubuntu and Yocto, BUT not from my Mac. Since I do my development on the mac, it would be nice to get it working on the Mac.
Here's how I'm calling it:
sudo pppd /dev/tty.usbmodem336D376733381 115200 172.168.0.1:172.168.0.2 noauth debug
I get the following message back:
Mon Aug 23 15:55:51 2021 : publish_entry SCDSet() failed: Success!
So it seems to have failed...but with Success, haha :)
Any suggestions what this could be?
Please note that I have verified that /dev/tty.usbmodem336D376733381 is the correct device and has ppp related data coming from it.
Thanks,
Craig
Ok, I figured out what my issue was. I was using two FTDI serial converters connected like a null modem cable:
I did not have the flow control lines connected (because that would require soldering). In the man page for pppd, I saw that hardware flow control is ON by default. Since I didn't have those line connected, flow control was preventing data from flowing resulting in the error I was getting. I added the "nocrtscts" option to my pppd command and it now works. The command I ended up with is:
sudo pppd /dev/tty.usbmodem336D376733381 115200 172.168.0.1:172.168.0.2 noauth nocrtscts
Related
I'm trying to simply setup an Open Source Greenplum instance and have been hitting the same issue regarding GPFDIST for days! Simply put, I do a full installation from scratch on CentOS 7.6 (can provide further details regarding setup if needed) installing OS GPDB software version 5.18 with GPORCA disabled. Full command for the compile is:
./configure --prefix=/usr/local/gpdb --with-perl --with-python --with-libxml --with-gssapi --with-includes=/usr/local/gpdb/include --with-libs=/usr/local/gpdb/lib --disable-orca
This compiles successfully, and the following make/make install commands too complete without issue. The initialisation of the Greenplum database itself also succeeds, and I can then go into a database and create tables, insert data and run queries like normal.
But if I try to select from an external table, such as the following:
create external table test_external_table
(testing smallint
)
location ('gpfdist://mdw:8080/test_data.csv')
format 'csv' (header delimiter '|')
;
with GPFDIST run as follows:
gpfdist -d /home/gpadmin/test/ -p 8080 -l /home/gpadmin/greenplum/logs/gpfdist_log 2>&1 &
then I get two errors; one from the external table, and one from GPFDIST. These are as follows:
External Table Returns:
ERROR: connection with gpfdist failed for gpfdist://mdw:8080/test_data.csv. effective url: http://127.0.0.1:8080/test_data.csv. error code = 104 (Connection reset by peer) (seg0 slice1 127.0.0.1:6000 pid=27962)
GPFDIST Returns:
[1]+ Segmentation fault gpfdist -d /home/gpadmin/test -p 8080 -l /home/gpadmin/greenplum/logs/gpfdist_log 2>&1
I have removed everything that isn't on the OS GPDB GitHub installation guide (for a 'bare-bones' setup), so I don't think that is causing the issue. I have tried everything to do with the hostname and network firewall, and it's all perfect as far as I can see.
I have also downloaded the same version of GPDB (5.18) from Pivotal and installed that version on the same instance simultaneously, and GPFDIST works perfectly fine.
I have also tried OS GPDB 5.17, 6 beta and 7 beta, and I get the same issue for all of them.
Any ideas at all on what might be causing this is VERY much appreciated, as I'm slowly going insane trying to figure this out now.
Thank you very much in advance for any help.
-- Edit --
Okay.. Having nearly chewed my own arm off in sheer frustration at trying to install debuginfo stuff on CentOS 7, I've finally generated a core dump with gdb. I then run:
gdb -c core_dump.<pid>
and get the following output:
Core was generated by `gpfdist -d /home/gpadmin/test -p 8080 -l /home/gpadmin/greenplum/logs/gpfdist_log'.
Program terminated with signal 11, Segmentation fault.
#0 0x00007f4f2c07bdff in ?? ()
But I have absolutely no idea what that means... Totally honest, I'm a little over my head with this now and really am stuck on how to proceed.
The connection reset by peer only indicates that the other end of the socket had dropped (...in this case, gpfdist because it crashed out).
Setup your gpfdist and try a wget to a hosted file adding:
--header='X-GP-PROTO:0'
You will need to add the header to avoid having the request rejected.
Are you able to retrieve a file there? Or does that also crash out?
If that crashes out, it's nothing to do with the database - and you will likely need a core dump to determine what the segfault is about (r/w permissions, memory, ...).
I've finally managed to solve this issue. Should anyone come looking with a similar problem, make sure you are installing Libevent version 1.4[.15], and nothing above that.
I had 2.2.0 installed, and whilst Greenplum sees this as fine, it actually doesn't work for it. Unfortunately, I did have to do an entire system installation from scratch to seemingly get it to work, as just installing Libevent 1.4 on the old system with Greenplum already compiled did not work for me.
I was playing my game normally before the update, I was at Debian 9.3 Stretch.
After update I try to run the game with the same command.
bash start-tibia.sh
And Output this:
No protocol specified
QXcbConnection: Could not connect to display :0
Aborted
I don't know why this happening.
My system: enter image description here
Important if I run the application with a normal user it works, but with the root user isn't work.
Any helps would be appreciated. :B
-Melt
I am actually trying to figure out where the DBG("") prints are going when I do a music stream using bluez to my headset. So basically I want to know where all the bluez debug messages are getting printed, be it any kind of bluetooth operation. ex: scan, inquiry , connect and so on .
Hopefully someone can help me with this .
Thanks in advance .
I have no Ubuntu here at the moment, but this is the way it works on Fedora and I'm sure it is very similar on Ubuntu, especially the systemd-part:
enable debugging by adding a -d after
ExecStart=/usr/libexec/bluetooth/bluetoothd
in /usr/lib/systemd/system/bluetooth.service
Save, then:
$ systemctl daemon-reload
$ systemctl restart bluetooth
Now you get your information in /var/log/syslog
To add to datafridge's answer above, I didn't have /usr/lib/systemd/system/bluetooth.service in Ubuntu 16.04 with BlueZ 5.41.
The file was at /etc/systemd/system/bluetooth.target.wants/bluetooth.service and the entry to be modified was
ExecStart=/usr/lib/bluez5/bluetooth/bluetoothd –d
The logs can also be seen using
journalctl --unit=bluetooth -f
I am trying to run a remote mathematica kernel between two macs.
Under Kernel Configuration Options
For kernel program I have:
/Applications/Mathematica.app/Contents/MacOS/MathKernel
The arguments of MLOpen:
-LinkMode Listen
-LinkProtocol TCPIP
-LinkOptions MLDontInteract
The launch command is:
java -jar mathssh username#xxxxxx.dynamic.uiowa.edu /usr/local/bin/math -mathlink -LinkMode
Connect -LinkProtocol TCPIP -LinkName "linkname" -LinkHost ipaddress
When i use this remote kernel (for instance 2+2 does not give a result) I get the error message:
"The kernel Thomas Machine failed to connect to the front end. (Error = MLECONNECT). You should try running the kernel connection outside the front end."
It seems that Mathematica is not even opening on the remote machine since I used "top" and do not see it running after I start the remote kernel.
Any help would be greatly appreciated.
I just tried this with 8.0.1 -- here's my config (with bogus machine/user names):
In particular the /usr/local/bin/math looks suspicious. You generally shouldn't need to use the advanced settings.
Drop to a command line and try:
ssh username#xxxxxx.dynamic.uiowa.edu /usr/local/bin/math
and see if you get a Mathematica prompt and can evaluate 1+1 there.
I've installed the mozrepl add-on in Firefox for Mac OS X, but any attempt to use WWW::Mechanize::Firefox fails in new() with the message
Failed to connect to , pattern match timed-out at /Library/Perl/5.10.0/MozRepl/Client.pm line 151
My speculation is that it has to do with mozrepl's default port, 4242. If in Terminal I type
telnet LOCALHOST 4242
I get garbage and no repl prompt. On the other hand if I tell mozrepl to use port 4241 and telnet to that port, I do not get garbage and I do get the repl prompt. I think my backup software, CrashPlan, is using 4242.
But if this is indeed the problem, and if I need to tell WWW::Mechanize::Firefox to use a different port, I can't figure out how to do so.
Try
$ENV{MOZREPL} = 'localhost:4241';
as per perldoc MozRepl::RemoteObject
FWIW, as old as this question is, this was the right answer for me tonight: How do you give WWW::Mechanize::Firefox permission to launch Firefox? I link it here because this was what I found first from Google and the ENV answer was not efficacious.