Marcus Hall

This page is read only. You can view the source, but not change it. Ask your administrator if you think this is wrong.
====== OpenSuse ======

------------------------------------------------------------------------------------------------------------------------------------------------\\

====== Configuring firewall ports ======


<WRAP center round box >
**Command line open ports in firewall**

sudo firewall-cmd --zone=public --add-port=5000/tcp 


https://forums.opensuse.org/showthread.php/533831-Opening-ports-in-the-new-YaST2-Firewall
</WRAP>


<WRAP center round box >
**Use Yast to configure open ports in firewall or turn firewall off**
 
    * what ports are open using vsftpd
      * firewall-cmd --permanent --service=vsftpd --get-ports
        * 21/tcp 30000-30100/tcp
    * what ports are open using Samba
      * firewall-cmd --permanent --service=samba --get-ports
        * 137/udp 138/udp 139/tcp 445/tcp
    * Reference: man firewall-cmd
</WRAP>

====== Hyper-v Video Resolution ======

<WRAP center round box >
2021-01-23

Works on grub

Set resolution

Find the line starting with GRUB_CMDLINE_LINUX_DEFAULT (line is highlight on image) and add video=hyperv_fb:[the resolution you need]
ex:- video=hyperv_fb:1200×700
you may need to change the above value several time to achieve better screen size. 1200×700 is the value which is worked on my 1366×768 resolution windows server.

[[https://www.tectut.com/wp-content/uploads/2015/02/1.png]]


[[https://www.tectut.com/2015/02/changing-linux-screen-resolution-in-hyper-v-virtual-machine/]]

</WRAP>

====== Hyper-V Synthetic Video Frame Buffer Driver ======


<WRAP center round box >
This is the driver for the Hyper-V Synthetic Video, which supports
 * screen resolution up to Full HD 1920x1080 with 32 bit color on Windows
 * Server 2012, and 1600x1200 with 16 bit color on Windows Server 2008 R2
 * or earlier.

[[https://github.com/torvalds/linux/blob/master/drivers/video/fbdev/hyperv_fb.c]]

</WRAP>


====== Configures video settings for virtual machines PowerShell ======


Set-VMVideo

Module: 
    Hyper-V

Configures video settings for virtual machines.
Syntax
PowerShell

Set-VMVideo
   [-CimSession <CimSession[]>]
   [-ComputerName <String[]>]
   [-Credential <PSCredential[]>]
   [-VMName] <String[]>
   [[-ResolutionType] <ResolutionType>]
   [[-HorizontalResolution] <UInt16>]
   [[-VerticalResolution] <UInt16>]
   [-Passthru]
   [-WhatIf]
   [-Confirm]
   [<CommonParameters>]
====== Resilio Sync ======

2020-09-05

<WRAP center round box >
Enable auto start at boot time using the following command:

$ sudo systemctl enable resilio-sync

5. Start Resilio Sync, use systemctl command.

$ sudo systemctl start resilio-sync

Check its status.

$ systemctl status resilio-sync

From: https://kenfavors.com/code/how-to-install-resilio-sync-on-ubuntu-16-04-using-vagrant/

</WRAP>




====== Reference ======

http://en.wikipedia.org/wiki/Rsyslog


====== Bridging networks ======

2020-07-16

<WRAP center round box >
Bridging networks

Packets not moving through linux ethernet bridge

This is a quite old question, but it might be helpful for others.
Linux bridge might drop packages, if not configured correctly. I had a likewise problem and could solve it with the following information: 
	• https://serverfault.com/questions/347676/linux-bridge-brctl-is-dropping-packets
	• https://superuser.com/questions/1211852/why-linux-bridge-doesnt-work
In short, there are options to configure the bridge: e.g.
# do not query iptables for package routing
    echo 0 > /proc/sys/net/bridge/bridge-nf-call-iptables
# no additional processing for multicast packages
    echo 0 > /sys/devices/virtual/net/br0/bridge/multicast_querier
    echo 0 > /sys/devices/virtual/net/br0/bridge/multicast_snooping


From <https://unix.stackexchange.com/questions/272146/packets-not-moving-through-linux-ethernet-bridge> 

From <https://unix.stackexchange.com/questions/272146/packets-not-moving-through-linux-ethernet-bridge> 
</WRAP>

<WRAP center round box >

    echo 0 > /proc/sys/net/bridge/bridge-nf-call-iptables
    echo 0 > /proc/sys/net/bridge/bridge-nf-call-ip6tables


Linux: Disabling Multicast snooping on bridges
Snooping should be enabled on either the router / switch or on the linux bridge, but it may not work if enabled on both. If you have a hosting provider that has igmp snooping enabled on the multicast switch, it may be necessary to disable snooping on the linux bridge. In that case use:
  post-up ( echo 1 > /sys/devices/virtual/net/$IFACE/bridge/multicast_querier )
  post-up ( echo 0 > /sys/class/net/$IFACE/bridge/multicast_snooping )


From <https://pve.proxmox.com/wiki/Multicast_notes> 
</WRAP>

<WRAP center round box >
Default for OpenSuse 15.1
   0 for  /sys/devices/virtual/net/br0/bridge/multicast_querier
   1 for /sys/devices/virtual/net/br0/bridge/multicast_snooping

Bring the bridge up
Like the Ethernet interfaces, the bridge will not become operational until it is brought into the ‘up’ state. This can be done for all three of these devices using the ifconfig command:
    ifconfig eth0 up
    ifconfig eth1 up
    ifconfig br0 up



From <http://www.microhowto.info/howto/bridge_traffic_between_two_or_more_ethernet_interfaces_on_linux.html> 
</WRAP>

<WRAP center round box >
2.1. Using "ip"
Usage: 
    ip link set dev <interface> up
    ip link set dev <interface> down
Example:

    ip link set dev eth0 up
    ip link set dev eth0 down


From <https://tldp.org/HOWTO/Linux+IPv6-HOWTO/ch05s02.html> 
</WRAP>

<WRAP center round box >

To set an interface to promiscuous mode you can use either of these commands, using the ‘ip’ command is the most current way.

   ip link set [interface] promisc on


From: https://www.thegeekdiary.com/how-to-configure-interface-in-promiscuous-mode-in-centos-rhel/
</WRAP>

<WRAP center round box >

{{ :software:linux:tcpdump.pdf |tcpdump Cheat Sheet}}

**D.3. tcpdump: Capturing with “tcpdump” for viewing with Wireshark**\\ 
It’s often more useful to capture packets using tcpdump rather than wireshark. For example, you might want to do a remote capture and either don’t have GUI access or don’t have Wireshark installed on the remote machine.
Older versions of tcpdump truncate packets to 68 or 96 bytes. If this is the case, use -s to capture full-sized packets:
    $ tcpdump -i <interface> -s 65535 -w <file>
You will have to specify the correct interface and the name of a file to save into. In addition, you will have to terminate the capture with ^C when you believe you have captured enough packets

From <https://www.wireshark.org/docs/wsug_html_chunked/AppToolstcpdump.html> 

**Comments**\\ 
https://www.wireshark.org/docs/man-pa... json JSON file format. It can be used with -j or -J including the JSON filter or with -x option to include raw hex-encoded packet data. Example of usage:
  tshark -T json -r file.pcap
  tshark -T json -j "http tcp ip" -x -r file.pcap

From: <https://ask.wireshark.org/question/12850/command-line-tshark-json-and-packet-details-all-expanded/> 



</WRAP>

====== rsyslog ======

------------------------------------------------------------------------------------------------------------------------------------------\\



<WRAP center round box >
http://www.rsyslog.com/

http://loganalyzer.adiscon.com/

http://en.wikipedia.org/wiki/Rsyslog


</WRAP>
=== Properties ===

<WRAP center round box >
http://www.rsyslog.com/doc/property_replacer.html

</WRAP>

=== Changes to setup a log for mediatrix ===

<code>File: /etc/rsyslog.d/remote.conf</code>

<code># UDP Syslog Server:
$ModLoad imudp.so  # provides UDP syslog reception
$UDPServerRun 514 # start a UDP syslog server at standard port 514

########### Mediatrix Log ##########
if ($fromhost-ip == '192.168.0.240') then /var/log/mediatrix
</code>

=== Additional Info ===

<code>
ps aux | grep -i rsyslog

netstat -an | grep 514
</code>



====== How do you display POST data with cURL? ======

From: https://superuser.com/questions/291424/how-do-you-display-post-data-with-curl

<code>
The closest I got without using tcpdump is using the --trace-ascii option:

~ curl http://w3.org/ -d "hello=there" --trace-ascii /dev/stdout
== Info: About to connect() to w3.org port 80 (#0)
== Info:   Trying 128.30.52.45... == Info: connected
== Info: Connected to w3.org (128.30.52.45) port 80 (#0)
=> Send header, 210 bytes (0xd2)
0000: POST / HTTP/1.1
0011: User-Agent: curl/7.19.7 (universal-apple-darwin10.0) libcurl/7.1
0051: 9.7 OpenSSL/0.9.8l zlib/1.2.3
0070: Host: w3.org
007e: Accept: */*
008b: Content-Length: 11
009f: Content-Type: application/x-www-form-urlencoded
00d0: 
=> Send data, 11 bytes (0xb)
0000: hello=there

</code>

====== OpenSuse Guide ======

From: https://doc.opensuse.org/documentation/leap/reference/html/book.opensuse.reference/cha.advdisk.html

Also Filesystems: https://www.suse.com/documentation/sles-12/singlehtml/stor_admin/stor_admin.html

<code>
For 42.3
This manual gives you a general understanding of openSUSE® Leap. It is intended mainly for system administrators and home users with basic system administration knowledge. Check out the various 
parts of this manual for a selection of applications needed in everyday life and in-depth 
descriptions of advanced installation and configuration scenarios.

</code>

From: http://opensuse-guide.org/switching.php

<code>
These are some examples of gratis applications available for both GNU/Linux and MS Windows for common 
tasks - most of them are available for Mac OSX too
</code>
====== Backup ======

From: https://forums.opensuse.org/content.php/202-Quick-Upgrade-from-Leap-42-2-to-Leap-42-3

<code>
I use the easy but accurate copy function "cp" to back up my root and home directories. 
You can use any partition to store backups, so long as you use appropriate Linux file 
system (so that the ownership and other file parameters are carried across faithfully). 
You can also store a backup on USB provided you format it for Linux.

Whenever I copy my root partition to backup, I do that outside of the running operating 
system, in this case Leap 42.2. So I boot into a live Linux cd or usb stick to do the job. 
You can use Knoppix or Gparted, Parted Magic, Ultimate Boot CD etc.

Once you are running in the live CD/USB you can mount the storage partition and use a command 
line like "cp -auv" to do the backup. But be sure to do it as su. (IMHO Knoppix is the best 
available at this time, and the mounting there is so super easy using Knoppix's gparted tool). 
</code>


====== Quick Upgrade from Leap 42.2 to Leap 42.3 ======

From: https://forums.opensuse.org/content.php/202-Quick-Upgrade-from-Leap-42-2-to-Leap-42-3

<code>
Alter the Repositories to become 42.3

Once you have the backup done, boot back into the real Leap 42.2 and edit the existing 
Repositories using Yast. Go to Yast ==> Software ==> Software Repositories. For each Repo 
you see bearing 42.2 in the name and/or URL, click to "edit" and change the instances of 
42.2 in Name and URL to 42.3 in Name and URL.

Optional: download the Leap 42.3 DVD and add it in as a repository (using Yast ==> 
Software ==> Software Repositories ==> Add ==> DVD ==> Next). Adding the DVD will 
speed the process.

</code>

====== openSUSE Leap 42.1 Tips, Tricks, and Tweaks ======

From: https://tweakhound.com/2015/11/10/opensuse-leap-42-1-tips-tricks-and-tweaks/

<code>
Dual-Boot
Dual Boot openSUSE Leap and Windows 10 UEFI

Multimedia
Every guide I’ve seen so far does not install enough stuff to cover all the bases. Below is 
everything I install.
</code>

====== Reloading NVIDIA Drivers openSuse ======


From: https://forums.opensuse.org/showthread.php/510615-Leap-42-desktop-freeze

<code>
try installing the nvidia drivers
zypper ar -f ftp://download.nvidia.com/opensuse/leap/42.1/ nvidia
zypper ref
zypper in x11-video-nvidiaG03

zypper ar -f ftp://download.nvidia.com/opensuse/leap/42.1/x86_64/ x11-video-nvidiaG04-352.55-17.1.x86_64.rpm
zypper ref
zypper in x11-video-nvidiaG04
</code>

====== sysinfo: in Konquer ======

From: https://tweakhound.com/2014/11/14/opensuse-13-2-tips-tricks-and-tweaks/

<code>
Get Sysinfo Back
Add repo: http://download.opensuse.org/repositories/KDE:/Extra/openSUSE_13.2/
Install: kio-sysinfo
In Konqueror (NOT Dolphin), go to address sysinfo: (or sysinfo://)
</code>

====== VNC Server installation on OpenSuse 13.2 ======

From: https://www.howtoforge.com/tutorial/vnc-server-on-opensuse-13.2/

<code>
kdenetwork3-vnc, select the software and install it:
Yast utility goto Network Service --> Remote Administration (VNC)
</code>

====== smbpasswd Add user, Change Password, Delete User ======

<code>
Note: add as passwd user first !

Add User - requires the user to already exist in the system password file
machine:~ # smbpasswd –a agustin
 New SMB password: ********
 Retype new SMB password:********

Change Password
machine:~ # smbpasswd agustin
 New SMB password: ********
 Retype new SMB password:********

Delete User
machine:~ # smbpasswd –x agustin
 Deleted user agustin
</code>


====== Windows + OpenSuse dual boot configuring GRUB ======

From: http://www.od2dev.be/windows-opensuse-dual-boot-configuring-grub/

<code>
#OpenSuse 11.2
title openSUSE 11.2 – 2.6.31.8-0.1
root (hd0,1)
kernel /boot/vmlinuz-2.6.31.8-0.1-default root=/dev/disk/by-id/ata-WDC_WD3000HLFS-01G6U1_WD-WXE0C7912926-part2 resume=/dev/disk/by-id/ata-WDC_WD3000HLFS-01G6U1_WD-WXE0C7912926-part1 splash=silent quiet showopts vga=0x31a
initrd /boot/initrd-2.6.31.8-0.1-default

#Windows7
title windows7
map (hd0) (hd2)
map (hd2) (hd0)
rootnoverify (hd2,0)
chainloader +1
</code>

====== Cloning the Disk and Setting-up GRUB ======

From: https://forums.opensuse.org/showthread.php/446597-cloning-boot-hard-drive-how-i-installed-new-replacement-hard-drive

<code>
At this reboot the system was still using the MBR of the old HDD but the new HDD for / and /home directories. Again using Yast – Boot Loader the GRUB files where changed to point only to the new HDD. With these changes made Yast – Bootloader “Propose new configuration” was used and accepted. Yast then generated the MBR and new initrd on the new HDD.

GRUB files => /boot/grub/device.map, /boot/grub/menu.1st and /etc/grub.conf.
Also: fstab


Note:  by-id, by-path, by-uuid 
</code>

From: https://www.suse.com/documentation/sles11/book_sle_admin/data/sec_grub_basic.html

<code>
GRUB comprises two stages. Stage 1 consists of 512 bytes and its only task is to load the 
second stage of the boot loader. Subsequently, stage 2 is loaded. This stage contains the 
main part of the boot loader.
</code>

From: https://forums.opensuse.org/showthread.php/446597-cloning-boot-hard-drive-how-i-installed-new-replacement-hard-drive

<code>
I determined that I needed to modify the /boot/grub/device.map, /boot/grub/menu.lst & /etc/fstab files 
and I had to insert the /dev/sdb2 or /dev/sdb for device.map, so that the new hard drive, which did not
 have the same uid name as the old drive, could boot openSUSE properly. Once I made these changes, 
the new drive did boot and openSUSE did come up.
GRUB files => /boot/grub/device.map, /boot/grub/menu.1st and /etc/grub.conf.
</code>

From: http://www.od2dev.be/windows-opensuse-dual-boot-configuring-grub/

<code>
Windows + OpenSuse dual boot configuring GRUB
</code>

From: https://administratosphere.wordpress.com/2011/04/02/an-easier-way-to-mount-disks-in-linux-by-uuid/

<code>
An Easier Way to Mount Disks in Linux (by UUID)
</code>

From: https://liquidat.wordpress.com/2013/03/13/uuids-and-linux-everything-you-ever-need-to-know/

<code>
UUIDs and Linux: Everything you ever need to know
</code>
====== How To Find Out What My DNS Servers Address Is ======

From: http://www.cyberciti.biz/faq/how-to-find-out-what-my-dns-servers-address-is/

linux dns

<code>
cat /etc/resolv.conf
</code>

====== Installation Packages ======

[[http://blogs.zdnet.com/perlow/?p=9716|Installation Packages]]


====== Automatically mount cifs ======

  * [[http://www.mail-archive.com/opensuse@opensuse.org/msg24138.html|Automatically mount cifs]]

  * [[http://lars-hilse.de/blog/2008/07/27/automatically-mount-a-windows-share-at-boot-time-in-opensuse-1/|Mount in fstab]]

  * [[http://rockpenguin.wordpress.com/2008/11/01/automount-smb-share-on-opensuse-how-i-got-squeezecenter-to-read-from-a-smb-share/|Mount in boot script]]

  * [[http://forums.novell.com/novell-product-support-forums/suse-linux-enterprise-desktop-sled/sled-networking/330900-im-not-getting-something-about-mount.html|Mount in fstab]]
    * %%//192.168.44.100/share_name /path_to/mount_point cifs
username=server_user,password=server_password,_netdev,uid=client_username,gid=users 0 0%%
    * Mounts with root access only

  * [[http://opensuse.swerdna.org/|Swerdna Guide]]

====== linuxtopia.org opensuse11.1_reference_guide ======


http://www.linuxtopia.org/online_books/opensuse_guides/opensuse11.1_reference_guide/index.html


  * [[http://www.novell.com/coolsolutions/feature/15354.html|Mount in Pam]]

====== Debug Scripts ======

From: email

* When debugging scripts, I add printf commands that write to a log file 
so I can review the log to confirm what the script did. For some 
scripts, I leave the printf there all of the time for ease of 
troubleshooting. Here's an example: 

     printf "\nAbout to do X and Y --- `date`\n" | tee -a /home/username/My_Log.txt 

====== Force fsck next reboot ======

From: http://www.ducea.com/2008/10/24/linux-tips-force-fsck-run-during-the-next-reboot/

    If for some reason, you want to force the system to run fsck on the next reboot just create an 
    empty file called forcefsck in your system / like this:

    touch /forcefsck

    OR

    at command prompt  shutdown with -F does it

    shutdown -rF now


====== Run fsck on mounted disk ======

From: http://forums.opensuse.org/english/get-technical-help-here/hardware/415871-how-run-fsck-manualy.html

    Additionally fsck should never be issued on a mounted partition. fsck should always be issued when the 
    disk is offline (not mounted).
    You need to specify the partition to check as the argument, e.g. {{{fsck /dev/sda1}}}

====== openSuse 12 uses rsyslog ======

    /etc/rsyslog.conf
    /etc/rsyslog.d/*conf is not setup by default
    
    note: vsftp writes to its own log = #vsftpd_log_file=/var/log/vsftpd.log
    
====== openSuse logrotate ======

<code>

/etc/logrotate.d

/var/log/vsftpd.log {
    weekly
    sharedscripts
    missingok
    notifempty
    postrotate
    /etc/init.d/vsftpd restart > /dev/null 2>&1 || true
    endscript
}
</code>

====== Chapter 2. System Monitoring Utilities ======

From: https://activedoc.opensuse.org/de/node/1184 


====== systemctl and systemd ======

  * **Enable postfix.service**
    * {{{systemctl enable postfix.service}}}
    * Postfix runs at level 3 and 5
    * postfix automatically starts


**difference between service and systemctl**

From: http://forums.fedoraforum.org/showthread.php?t=261945

    service operates on the files in /etc/init.d and was used in conjunction with the old init system. 
    systemctl operates on the files in /lib/systemd . If there is a file for your service in /lib/systemd 
    it will use that first and if not it will fall back to the file in /etc/init.d

**systemctl**

http://fedoraproject.org/wiki/Systemd

http://crashmag.net/useful-systemd-commands

**List the current run level**

    systemctl list-units --type=target

**system-analyze**

    {{{/usr/bin/systemd-analyze
    /usr/bin/systemd-analyze plot
    /usr/bin/systemd-analyze blame
    /usr/bin/systemd-analyze time
    systemctl dot --order | dot -Tsvg > /root/Desktop/systemd.svg
    }}}

From: http://0pointer.de/blog/projects/systemd-for-admins-2.html

[[fedoraproject.org wiki Systemd>>http://fedoraproject.org/wiki/Systemd]]

**Systemd_Cheatsheet**
 

From: http://fedoraproject.org/wiki/SysVinit_to_Systemd_Cheatsheet


====== systemd timers can be used to perform the same kinds of tasks as the cron ======

<WRAP center round box >
2020-07-23

Summary
systemd timers can be used to perform the same kinds of tasks as the cron tool but offer more flexibility in terms of the calendar and monotonic time specifications for triggering events.
Even though the service unit you created for this experiment is usually triggered by the timer, you can also use the systemctl start myMonitor.service command to trigger it at any time. Multiple maintenance tasks can be scripted in a single timer; these can be Bash scripts or Linux utility programs. You can run the service triggered by the timer to run all the scripts, or you can run individual scripts as needed.

From <https://opensource.com/article/20/7/systemd-timers?utm_medium=Email&utm_campaign=weekly&sc_cid=7013a000002glehAAA> 

^• Rethinking PID 1                      |http://0pointer.de/blog/projects/systemd.html|
^• systemd for Administrators, Part I    |http://0pointer.de/blog/projects/systemd-for-admins-1.html|
^• systemd for Administrators, Part II   |http://0pointer.de/blog/projects/systemd-for-admins-2.html|
^• systemd for Administrators, Part III  |http://0pointer.de/blog/projects/systemd-for-admins-3.html|
^• systemd for Administrators, Part IV   |http://0pointer.de/blog/projects/systemd-for-admins-4.html|
^• systemd for Administrators, Part V    |http://0pointer.de/blog/projects/three-levels-of-off.html|
^• systemd for Administrators, Part VI   |http://0pointer.de/blog/projects/changing-roots|
^• systemd for Administrators, Part VII  |http://0pointer.de/blog/projects/blame-game.html|
^• systemd for Administrators, Part VIII |http://0pointer.de/blog/projects/the-new-configuration-files.html|
^• systemd for Administrators, Part IX   |http://0pointer.de/blog/projects/on-etc-sysinit.html|
^• systemd for Administrators, Part X    |http://0pointer.de/blog/projects/instances.html|
^• systemd for Administrators, Part XI   |http://0pointer.de/blog/projects/inetd.html|

From <https://opensource.com/article/20/7/systemd-timers?utm_medium=Email&utm_campaign=weekly&sc_cid=7013a000002glehAAA> 
</WRAP>



====== Graphic Cards ======


<WRAP center round box >
2019-01-27

openSUSE Graphic Card Practical Theory Guide for Users

Look for occurrences of:
(==) NOUVEAU(0):
which would indicate open source NOUVEAU driver in use.The following command may work (note syntax/spaces) to confirm this driver:
Code:
cat /var/log/Xorg.0.log | grep '('II')'' 'NOUVEAU

From: <https://forums.opensuse.org/showthread.php/430150-openSUSE-Graphic-Card-Practical-Theory-Guide-for-Users?p=2157771#post2157771> 

</WRAP>