Enabling Dual-Channel for RAM

 cf: Dual Channel

Installing RAM modules on A1 and B1 will enable dual-channel mode as well as A2 and B2. However, installing them in A1 and A2 will make them run in single-channel mode.

Change page size to 16:9

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Reinstall samba

sudo purge samba

sudo remove samba

sudo aptitude to reinstall samba

Matplotlib error due to font size: type1ec.sty not found

sudo apt install cm-super

mount image img file

 cf: https://coldnew.github.io/ff159f7c/

1. sudo fdisk -u -l pi3_20221116.img
   The outputs are
   ...
   所用裝置          可開機  Start     結束     磁區  Size Id 類型
   pi3_20221116.img1          8192   532480   524289  256M  c W95 FAT32 (LBA)
   pi3_20221116.img2        540672 30881791 30341120 14.5G 83 Linux
   
   Get the Start block 540672 for partition 2
2. sudo mount -o loop,offset=$((540672 * 512)) pi3_20221116.img /mnt/myimg

The script file: (cf: https://github.com/AlexanderAmelkin/mountimg/blob/master/mountimg) 

#!/bin/bash
IMAGE="$1"
PART="$2"
WHERE="$3"
shift 3

OPTIONS="$*"

if [ ! -f "$IMAGE" ] || [ -z "$PART" ] || [ -z "$WHERE" ]; then
    echo "Disk image partition mounter by Alexander Amelkin."
    echo "Version 1.0"
    echo
    echo "Usage: mountimg <image> <partition> <where> [<mount options>]"
    echo "Example: mountimg sdcard.img 1 /mnt/sdcard0p1 -t vfat -o ro,codepage=866,iocharset=utf-8"
    exit 1
fi

# Now find the first unused loop device and use it
OFFSET=$(
    sfdisk -l $IMAGE |
    grep $IMAGE$PART |
    awk 'BEGIN { FS="[ *\t]+"}
         /.+/ { print $2; found=1 }
         END { if(!found) exit 1 }'
    ) || { echo "No such partition in the image"; exit 1; }

echo "Mounting $IMAGE partition $PART (offset $OFFSET) to $WHERE via $LODEV"

set -e

mount $OPTIONS -o loop,offset=$((OFFSET * 512)) $IMAGE $WHERE

PhpOffice\PhpSpreadsheet\Spreadsheet' not found

composer require phpoffice/phpspreadsheet

You have requested a non-existent service "user.private_tempstore"

Change this line:

$tempstore = \Drupal::service('user.private_tempstore')->get('appraisal_edit');

into

$tempstore = \Drupal::service('tempstore.private')->get('appraisal_edit');

Disable php7.4-fpm.conf, enable php8.1-fpm.conf

sudo a2disconf php7.4-fpm.conf
sudo a2enconf php8.1-fpm.conf

Upgrade Mac OS X stuck hung at progress bar

cf: https://www.sysprobs.com/macos-13-ventura-vmware-pre-installed-image-download-windows-11-10 

This links also contains the download urls for Ventura vmware image (worked!)

1. Poweroff the virtual guest (not workstation)
2. Add this line into vmx file, e.g. Monterey.vmx
   smc.version= "0" 
3. Change the line as follows:
   #ethernet0.virtualDev = "e1000e"
   ethernet0.virtualDev = "vmxnet3"
4. Save and restart guest.
5. If it is successfully opened, but the mouse and keyboard are not working, then change the USB version in VM settings to USB3.1.
6. Viola!

 

Upgrade Mac OS Ventura

cf: https://mrmacintosh.com/macos-ventura-13-full-installer-database-download-directly-from-apple/

Download  InstallAssistant.pkg

 

Mathematica installation error

 cf: https://askubuntu.com/questions/422026/mathematica-installation-problem

Don't use directory/folder name with space

Safely power off USB drive

1. Umount all: e.g
   sudo umount /media/pi/ntfs_1TB
   sudo umount /media/pi/ext4_1.7TB
   sudo umount /media/pi/ext4_1TB
   
2. sudo udisksctl power-off -b /dev/sda

Disable "wake on pattern match"

cf: https://superuser.com/questions/560175/what-does-wake-on-pattern-match-option-mean-in-network-card-preferences 

Disable "wake on pattern match" to prevent my vmware on kpchiao9600k to wake up win10 on kpchiaoamd.

 

Rsyslogd: action ‘action-0-builtin:omfile’ ‘action-7builtin:omfile’

cf: https://ubuntu-mate.community/t/rsyslogd-action-action-0-builtin-omfile-resumed-module-builtin-omfile/24105

Edit /etc/rsyslog.conf and comment the following lines.

#
# Set the default permissions for all log files.
#
#$FileOwner syslog
#$FileGroup adm
#$FileCreateMode 0640
#$DirCreateMode 0755
#$Umask 0022
#$PrivDropToUser syslog
#$PrivDropToGroup syslog

Restart rsyslog

 

Set network interface priority

cf: https://forums.raspberrypi.com/viewtopic.php?t=278033  

For linux: 

First run the command:

route -n 

It will show the metrics of the interface. 

Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         192.168.2.1     0.0.0.0         UG    202    0        0 eth1
0.0.0.0         192.168.1.12    0.0.0.0         UG    303    0        0 wlan0
 

The lower the route priority first. So eth0 is higher than wlan0.

Edit /etc/dpchcd.conf: 

interface wlan0 

metric 100 

And run route -n, it will then show:


 

Kernel IP routing table 

Destination Gateway Genmask Flags Metric Ref Use Iface


0.0.0.0 192.168.1.12 0.0.0.0 UG 100 0 0 wlan0 

0.0.0.0 192.168.2.1 0.0.0.0 UG 204 0 0 eth1  

 

Thus, wlan0 will is higher than eth1. 

Becuase wlan0 is the external interface, while eth1 is for internal interface, the wlan0 priority need to be higher than eth1. Otherwise, the outside internet can not be reached. 

 

For windows:

The following image shows the NIC is set to metric 5.


 

lyx cannot show pdf figure

cf: https://stackoverflow.com/questions/52998331/imagemagick-security-policy-pdf-blocking-conversion

Due to  ImageMagick security policy, just remove the lines from /etc/ImageMagick-6/policy.xml:

<!-- disable ghostscript format types -->
<policy domain="coder" rights="none" pattern="PS" />
<policy domain="coder" rights="none" pattern="PS2" />
<policy domain="coder" rights="none" pattern="PS3" />
<policy domain="coder" rights="none" pattern="EPS" />
<policy domain="coder" rights="none" pattern="PDF" />
<policy domain="coder" rights="none" pattern="XPS" /> 

table uppercase capitalized

 Put \def\tablename{TABLE} in front of Table, e.g.

 

Then the output is