Transmission network problem

Recently started in debug mode on Transmission and I see:

[17:42:40.319] UDP Failed to set receive buffer: requested 4194304, got 262142 (tr-udp.c:75)
[17:42:40.319] UDP Please add the line "net.core.rmem_max = 4194304" to /etc/sysctl.conf (tr-udp.c:80)
[17:42:40.319] UDP Failed to set send buffer: requested 1048576, got 262142 (tr-udp.c:86)
[17:42:40.319] UDP Please add the line "net.core.wmem_max = 1048576" to /etc/sysctl.conf (tr-udp.c:91)

By tuning the two variables, higher throughput can be achieved more easily using uTP.

Here’s the relevant part from the changeset :

Since we are using a single UDP socket to implement multiple UTP sockets,
and since we are not always timely in servicing an incoming UDP packet,
it is important to use a large receive buffer. The send buffer is probably
less critical, we increase it nonetheless.

Four megabytes might seem huge for embedded clients, but running behind a dedicated connection, it might even become too small. I recommend using 16 megabytes for receive buffering and 4 for the send buffer. That is, because uTP implements a retransmission algorithm and by scaling up the buffers we can achieve fewer retransmits because of dropped datagrams. Let’s set it up that way.

Check actual settings:

do the modifications:


Oracle 11g XE install on Ubuntu 14/16

After Ubuntu downloaded and installed.

First install Java:


Reload sources:


result should be:

Second: Download and prepare Oracle DB

Copy the downloaded file and paste it in home directory.

Unzip using the command:

Install required packages using the command:

Enter into the Disk1 folder using command:

Convert RPM package format to DEB package format (that is used by Ubuntu) using the command:

Create the required chkconfig script using the command:

The pico text editor is started and the commands are shown at the bottom of the screen. Now copy and paste the following into the file and save:

Change the permission of the chkconfig file using the command:

Set kernel parameters. Oracle 11gR2 XE requires additional kernel parameters which you need to set using the command:

Copy the following into the file and save:

Verify the change using the command:

You should see what you entered earlier. Now load the kernel parameters:

Verify the new parameters are loaded using:

You should see the file-max value that you entered earlier.

Set up /dev/shm mount point for Oracle. Create the following file using the command:

Copy the following into the file and save.

Change the permissions of the file using the command:

Now execute the following commands:

Install Oracle

Install the oracle DBMS using the command:

Configure Oracle using the command:

Setup environment variables by editting your .bashrc file:

Add the following lines to the end of the file:

Load the changes by executing your profile:

Start the Oracle 11gR2 XE:

Add user YOURUSERNAME to group dba using the command:


src: and

gentoo beragadt init script takarítása


Debian 8 Docker daemon default start params remove

Somebody at debian’s thought, it will be very usefull, if adds the

param to the docker daemon default

To remove it, and use the /etc/docker/daemon.json do this below:

mod this line:


than reload the daemon config

and reload the service



JDK 8 Failed to read schema document ‘xjc.xsd’, because ‘file’ access is not allowed due to restriction set by the accessExternalSchema property.

The error msg is:

java.lang.AssertionError: org.xml.sax.SAXParseException; systemId: jar:file:/path/to/glassfish/modules/jaxb-osgi.jar!/com/sun/tools/xjc/reader/xmlschema/bindinfo/binding.xsd; lineNumber: 52; columnNumber: 88; schema_reference: Failed to read schema document ‘xjc.xsd’, because ‘file’ access is not allowed due to restriction set by the accessExternalSchema property.

the resolution is:

Create a file named (if it doesn’t exist) under /path/to/jdk1.8.0/jre/lib and then write this line in it:


gigabit e1000e Detected Hardware Unit Hang

If we see it in

the resulution is:


for gentoo, add these lines into



Tomcat 8.5 manager app, manager-script role

Mert másodszor futottam bele. A tomcat 8.5 alap manager appjában változott (szigorodott) a jogosultság kezelés.

Az alábbi sort ki kell kommentezni:




MySQL root pwd reset

next start damon at safe mode

connect to the safe mode daemon into mysql database

change pwd


kill safe moded daemon

than restart deamon

test the new pwd



Adot napnál régebbi fájlok megkeresése


Pidgin facebook usage

Most useful solution:

Download, install (copy ddl-s), then restart. Done.