Unable to negotiate with X.X.X.X port XXXX : no matching key exchange method found. Their offer: diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group14-sha256,diffie-hellman-group1-sha1 [preauth]

KexAlgorithms +diffie-hellman-group14-sha256

ssh -Q KexAlgorithms

# Download the Ubuntu Server ISO using wget
wget https://releases.ubuntu.com/25.04/ubuntu-25.04-live-server-amd64.iso

# If you're creating a bootable USB from terminal 
sudo dd if=ubuntu-25.04-live-server-amd64.iso of=/dev/sdX bs=4M status=progress

# Update your current system first
sudo apt update && sudo apt upgrade -y

# Install the update-manager-core if not already installed
sudo apt install update-manager-core

# Edit the release upgrade settings to allow non-LTS upgrades
sudo nano /etc/update-manager/release-upgrades
# Change Prompt=lts to Prompt=normal

# Start the upgrade process
sudo do-release-upgrade -d

# Bring system up to date
sudo dnf upgrade --refresh

# Install DNF plugin for system upgrades (if not already present)
sudo dnf install dnf-plugin-system-upgrade

# Download the upgrade to Fedora 42
sudo dnf system-upgrade download --releasever=42

# Reboot system and perform upgrade
sudo dnf system-upgrade reboot

/srv/www/original/src
    sync to -> /srv/www/web1/src/ 
    sync to -> /srv/www/web2/src/

sudo apt install lsyncd    # Debian/Ubuntu
systemctl enable lsyncd

lsyncd --version

Version: 2.2.3

cat /etc/init.d/lsyncd | grep CONFIG=

CONFIG=/etc/lsyncd/lsyncd.conf.lua

vi /etc/lsyncd/lsyncd.conf.lua

settings {
    logfile = "/var/log/lsyncd.log",  
    statusFile = "/var/log/lsyncd-status.log"  
}
-- Synchronize directories
sync {
    default.direct,
    source = "/srv/www/original/src/",  
    target = "/srv/www/web1/src/",  
    delay = 1,
    exclude = {"css/*", "js/*"}  
}
sync {
    default.direct,
    source = "/srv/www/original/src/",  
    target = "/srv/www/web2/src/",  
    delay = 1,
    exclude = {"css/*", "js/*"}  
}

mkdir /srv/www/web1/src/
rsync -av --delete --exclude="css/" --exclude="js/" /srv/www/original/src/ /srv/www/web1/src/  
mkdir /srv/www/web2/src/
rsync -av --delete --exclude="css/" --exclude="js/" /srv/www/original/src/ /srv/www/web2/src/  

sudo systemctl restart lsyncd

sudo systemctl status lsyncd

● lsyncd.service - LSB: lsyncd daemon init script
     Loaded: loaded (/etc/init.d/lsyncd; generated)
     Active: active (running) since Tue 2025-03-18 12:44:25 CET; 3h 22min ago
       Docs: man:systemd-sysv-generator(8)
    Process: 246897 ExecStart=/etc/init.d/lsyncd start (code=exited, status=0/SUCCESS)
      Tasks: 1 (limit: 115371)
     Memory: 512.0M
        CPU: 3.791s
     CGroup: /system.slice/lsyncd.service
             └─246905 /usr/bin/lsyncd -pidfile /var/run/lsyncd.pid /etc/lsyncd/lsyncd.conf.lua

Mar 18 12:44:25 ares systemd[1]: Starting LSB: lsyncd daemon init script...
Mar 18 12:44:25 ares lsyncd[246897]:  * Starting synchronization daemon lsyncd
Mar 18 12:44:25 ares lsyncd[246904]: 12:44:25 Normal: --- Startup, daemonizing ---
Mar 18 12:44:25 ares lsyncd[246897]:    ...done.
Mar 18 12:44:25 ares systemd[1]: Started LSB: lsyncd daemon init script.

tail -f /var/log/lsyncd.log

tail -f /var/log/lsyncd-status.log

cat /proc/acpi/wakeup

Device	S-state	  Status   Sysfs node
GPP0	  S4	*enabled   pci:0000:00:01.1
GPP1	  S4	*disabled
GPP3	  S4	*disabled
GPP4	  S4	*disabled
GPP5	  S4	*disabled
GPP6	  S4	*disabled
GPP7	  S4	*disabled
GPP8	  S4	*enabled   pci:0000:00:03.1
GPP9	  S4	*disabled
GPPA	  S4	*disabled
GPPB	  S4	*disabled
GPPC	  S4	*disabled
GPPD	  S4	*disabled
GPPE	  S4	*disabled
GPPF	  S4	*disabled
GP10	  S4	*disabled
GP11	  S4	*disabled
GP12	  S4	*enabled   pci:0000:00:07.1
GP13	  S4	*enabled   pci:0000:00:08.1
XHC0	  S4	*enabled   pci:0000:0b:00.3
GP30	  S4	*disabled
GP31	  S4	*disabled
PS2K	  S3	*disabled
PS2M	  S3	*disabled
GPP2	  S4	*enabled   pci:0000:00:01.3
PTXH	  S4	*enabled   pci:0000:02:00.0

lsusb

Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 003: ID 0a12:0001 Cambridge Silicon Radio, Ltd Bluetooth Dongle (HCI mode)
Bus 001 Device 004: ID 25a7:fa0b Areson Technology Corp 2.4G Wireless Receiver
Bus 001 Device 009: ID 046d:c548 Logitech, Inc. Logi Bolt Receiver
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 002: ID 1038:12f6 SteelSeries ApS Arctis Nova 4X
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub

lsusb | grep -i logitech

Bus 001 Device 003: ID 046d:c548 Logitech, Inc. Logi Bolt Receiver

echo 'ACTION=="add", SUBSYSTEM=="usb", ATTRS{idVendor}=="046d", ATTRS{idProduct}=="c548", ATTR{power/wakeup}="disabled"' | sudo tee /etc/udev/rules.d/90-logibolt-disable-wakeup.rules > /dev/null  
echo 'ACTION=="add", SUBSYSTEM=="usb", ATTRS{idVendor}=="046d", ATTRS{idProduct}=="c548", ATTR{power/autosuspend}="0"' | sudo tee /etc/udev/rules.d/91-logibolt-power-management.rules > /dev/null  

sudo udevadm control --reload
sudo udevadm trigger

# Find the corresponding USB device path
for device in /sys/bus/usb/devices/*; do
  if grep -q "046d" "$device/idVendor" 2>/dev/null && grep -q "c548" "$device/idProduct" 2>/dev/null; then  
    echo "Logitech Bolt Receiver found at: $device"  
    
    # Check wake-up status
    if [ -f "$device/power/wakeup" ]; then  
      echo "Wake-up status: $(cat $device/power/wakeup)"  
    fi
    
    # Check autosuspend status
    if [ -f "$device/power/autosuspend" ]; then  
      echo "Autosuspend status: $(cat $device/power/autosuspend)"  
    fi
  fi
done

Logitech Bolt Receiver found at: /sys/bus/usb/devices/1-5
Wake-up status: disabled
Autosuspend status: 0

echo '[Unit]  
Description=Disable Logitech MX Mechanical Bolt Receiver wake-up
After=multi-user.target
[Service]
Type=oneshot
ExecStart=/bin/sh -c "echo PTXH > /proc/acpi/wakeup"  
RemainAfterExit=yes
[Install]
WantedBy=multi-user.target' | sudo tee /etc/systemd/system/disable-logibolt-wakeup.service > /dev/null  

sudo systemctl enable disable-logibolt-wakeup.service

cat /proc/acpi/wakeup | grep PTXH

PTXH	  S4	*disabled   pci:0000:02:00.0

sudo systemctl status disable-logibolt-wakeup.service

Rather than using a wildcard or programmatically verifying supplied origins, use a whitelist of trusted domains.

curl -I -X OPTIONS -H "Origin: https://DOMAIN.TLD" -H 'Access-Control-Request-Method: GET' https://DOMAIN.TLD/index.php 2>&1 | grep 'Access-Control-Allow-Origin'  

Access-Control-Allow-Origin: https://DOMAIN.TLD

frontend http_front
    bind *:80
    
    # CORS headers
    http-response set-header Access-Control-Allow-Origin "https://your-domain.com"  
    http-response set-header Access-Control-Allow-Methods "GET, POST, OPTIONS, PUT, DELETE"  
    http-response set-header Access-Control-Allow-Headers "Origin, X-Requested-With, Content-Type, Accept, Authorization"  
    http-response set-header Access-Control-Max-Age "3600"  
    
    # Optional: Handle OPTIONS preflight requests
    acl cors_preflight method OPTIONS
    http-request return status 204 if cors_preflight
    
    default_backend web_servers

backend web_servers
    server server1 127.0.0.1:8080 check

header("Access-Control-Allow-Orgin: https://rootdb.com");  
header("Access-Control-Allow-Methods: GET,POST");  

Access-Control-Allow-Origin: https://rootdb.com

sudo nano /etc/hosts

##
# Host Database
#
# localhost is used to configure the loopback interface
# when the system is booting.  Do not change this entry.
##
127.0.0.1       localhost
255.255.255.255 broadcasthost
::1             localhost

##
# Host Database
#
# localhost is used to configure the loopback interface
# when the system is booting.  Do not change this entry.
##
127.0.0.1       localhost
255.255.255.255 broadcasthost
::1             localhost

192.168.0.1 www.mydomain.com
192.168.0.2 mymac

dscacheutil -flushcache

# ping mymac
PING mymac (192.168.0.2): 56 data bytes
64 bytes from 192.168.0.2: icmp_seq=0 ttl=64 time=0.155 ms
64 bytes from 192.168.0.2: icmp_seq=1 ttl=64 time=0.166 ms

sudo nmcli con show
NAME                         UUID                                  TYPE      DEVICE 
Wired connection 1  7708dd93-ea55-398a-9dd1-b5be2c65d4b6  ethernet  enp4s0 
lo                           e6140168-f933-434b-883b-8095ee9b9488  loopback  lo     

sudo nmcli con mod 'Wired connection 1' ipv4.dns-search "searchdomain.tld"  

sudo nmcli con show 'Wired connection 1' | grep dns-search  

resolvectl

vi /etc/NetworkManager/system-connections/'Wired connection 1.nmconnection'  

[connection]
id=Wired connection 1
uuid=c0718bbc-fa2b-3be2-a863-4d946ffa16ff
type=ethernet
autoconnect-priority=-999
interface-name=enp5s0
timestamp=1740436074

[ethernet]

[ipv4]
dns=192.168.0.1;
dns-search=searchdomain.tld;
method=auto

[ipv6]
addr-gen-mode=default
method=auto

[proxy]

systemctl restart NetworkManager

sudo dnf install nmtui

[root@frank-endeavour ~]# nmtui

vi /etc/netplan/00-installer-config.yaml

network:
    ethernets:
        enp4s0:
            addresses:
            - 192.168.0.4/24
            dhcp4: false
            gateway4: 192.168.0.1
            nameservers:
                addresses:
                - 192.168.0.1
                search:
                - searchdomain.tld
    version: 2

sudo netplan generate
sudo netplan apply

/log print where (([:timestamp]+([/system clock get gmt-offset]."s"))-[:totime (time)]) < 1h  

/log print where [:totime (time)] >= [:totime [/system clock get date]]

/log print where [:totime (time)] > [:totime "2025-02-27 00:00:00"] && [:totime (time)] < [:totime "2025-02-28 00:00:00"]   

# output associative array using print with "as-value" 
:global MYLOG [/log print as-value where (([:timestamp]+([/system clock get gmt-offset]."s"))-[:totime (time)]) < 1h]  
# the same principle also can be used with find to just get the internal references for the entries
:global MYLOG [/log find (([:timestamp]+([/system clock get gmt-offset]."s"))-[:totime (time)]) < 1h]  

/log print where [:totime (time)] > [:totime "2025-02-27 00:00:00"] && [:totime (time)] < [:totime "2025-02-28 00:00:00"]  && message ~ "logged in"  

/ip firewall filter add chain=input protocol=tcp dst-port=22 action=accept place-before=([get ([find chain=input && connection-state ~ "established"]->0)]->".nextid")  

{
    :local rule ([/ip firewall filter find chain=input && connection-state ~ "established"]->0)  
    :if ($rule) do={
       /ip firewall filter add chain=input protocol=tcp dst-port=22 action=accept place-before=([get $rule]->".nextid")  
    } else={
       :error "Rule not found!"  
    }
}

C:\Users\username\AppData\Local\Microsoft\Edge

In general, you can only permanently delete the User Data folder if your Edge browser no longer starts or is broken.  Otherwise, there are open directories in the folder that cannot be deleted.

cd ~/Library/LaunchAgents

com.google.keystone.agent.plist
com.google.keystone.xpcservice.plist

rm com.google.keystone.*

cd /Library/LaunchAgents
cd /Library/LaunchDaemons

cd ~/Library/Google
ls -la

.~/Library/Google/GoogleSoftwareUpdate/GoogleSoftwareUpdate.bundle/Contents/Resources/ksinstall --uninstall
rm -r ~/Library/Google/

public static function stringCompare($str1, $str2): float {
        if ($str1 === $str2) return 0.0;

        $str1 = self::cleanString($str1);
        $str2 = self::cleanString($str2);

        if ($str1 === '' && $str2 === '') return 0.0;    
        if ($str1 === '' || $str2 === '') return 100.0;    

        $len1 = strlen($str1);
        $len2 = strlen($str2);

        // length change
        $lenChange = abs($len1 - $len2) / max($len1, $len2);

        // Improved detection of repeated text
        $repetitionFactor = 0;
        if (str_contains($str2, $str1) || str_contains($str1, $str2)) {
            $repetitions = max($len1, $len2) / min($len1, $len2);
            $repetitionFactor = 1 - (1 / $repetitions);
        }

        // character comparison
        $chars1 = count_chars($str1, 1);
        $chars2 = count_chars($str2, 1);
        $charDiff = 0;
        foreach (array_keys($chars1 + $chars2) as $i) {
            $charDiff += abs(($chars1[$i] ?? 0) / $len1 - ($chars2[$i] ?? 0) / $len2);
        }
        $charChange = $charDiff / 2;  // normalisation

        // comparison of words
        $words1 = str_word_count(mb_strtolower($str1), 1);
        $words2 = str_word_count(mb_strtolower($str2), 1);
        $wordCount1 = array_count_values($words1);
        $wordCount2 = array_count_values($words2);
        $wordDiff = 0;
        $allWords = array_unique(array_merge(array_keys($wordCount1), array_keys($wordCount2)));
        
        $count1 = count($words1);
        $count2 = count($words2);

        if ($count1 > 0 || $count2 > 0) {
            foreach ($allWords as $word) {
                $freq1 = $count1 > 0 ? ($wordCount1[$word] ?? 0) / $count1 : 0;
                $freq2 = $count2 > 0 ? ($wordCount2[$word] ?? 0) / $count2 : 0;
                $wordDiff += abs($freq1 - $freq2);
            }
            $wordChange = $wordDiff / 2;  // normalisation
        } else {
            // If no words are recognised, we only use the character comparison.
            $wordChange = $charChange;
        }

        // Weighted total change
        $overallChange = max(
            $lenChange,
            $repetitionFactor,
            ($charChange * 0.4 + $wordChange * 0.6)
        );

        return round(min($overallChange, 1.0) * 100, 2);
}

$str1 = "This is an example text for the comparison";    
$str2 = "xxxx xx xx xxxxxxx xxxx xxx xxx xxxxxxxxxx";    
echo "Percentage change (same position, replaced by x): " . TextComparison::stringCompare($str1, $str2) . "%\n";