Automatically start zram swap device on boot with systemd zram-generator under CentOS Stream 9

zram-generator package will install necessary tools to automate the creation on boot the compressed RAM devices. This article focuses on compressed swap devices.

main menu
install

As of writing this article, the latest version in the package system under CentOS Stream 9 is 0.32. The the latest version on the original page of the software is much higher number 1.1.2 and many of the following configuration options are marked as OBSOLETE, but they work in the 0.32 version included in CentOS Stream 9 (and the new configuration options does not!). That’s why it is important to check the included sample configuration file.
The package installs no configuration file, just a sample configuration file – /usr/share/doc/zram-generator/zram-generator.conf.example.
zram in the kernel space – https://docs.kernel.org/admin-guide/blockdev/zram.html

STEP 1) Install the zram-generator

It is easy and straightforward, just a single package:

[root@srv) ~]# dnf install -y zram-generator
Last metadata expiration check: 3:42:20 ago on Fri 20 Oct 2023 05:18:32 AM UTC.
Dependencies resolved.
==============================================================================================================
 Package                      Architecture         Version                      Repository               Size
==============================================================================================================
Installing:
 zram-generator               x86_64               0.3.2-7.el9                  appstream               409 k

Transaction Summary
==============================================================================================================
Install  1 Package

Total download size: 409 k
Installed size: 983 k
Downloading Packages:
zram-generator-0.3.2-7.el9.x86_64.rpm                                         2.1 MB/s | 409 kB     00:00    
--------------------------------------------------------------------------------------------------------------
Total                                                                         1.3 MB/s | 409 kB     00:00     
Running transaction check
Transaction check succeeded.
Running transaction test
Transaction test succeeded.
Running transaction
  Preparing        :                                                                                      1/1 
  Installing       : zram-generator-0.3.2-7.el9.x86_64                                                    1/1 
  Running scriptlet: zram-generator-0.3.2-7.el9.x86_64                                                    1/1 
  Verifying        : zram-generator-0.3.2-7.el9.x86_64                                                    1/1 

Installed:
  zram-generator-0.3.2-7.el9.x86_64                                                                           

Complete!

STEP 2) Create a configuration and start the service

By default, there is no configuration file. The best place for it is /etc/systemd/zram-generator.conf.
Here is an example, which will fulfill the following:

  • Set the maximum RAM of the system, because it is a hard-coded 9G, by default. And if not redefined the device will be with 9G max memory no matter how much is tuned by the other options.
  • Set the RAM of the compressed device.
  • Set the fraction of the ram, which may be used by the device. Again as with the above configuration option, it is important, because it limits the maximum available memory to allocate for the compressed device.
  • Set the type of the device – filesystem or swap device.

There is the real world example configuration – /etc/systemd/zram-generator.conf

[root@srv ~]# cat /etc/systemd/zram-generator.conf
[zram0]
host-memory-limit = none
max-zram-size = 32768
zram-fraction = 1.0
compression-algorithm = zstd
swap-priority = 100
fs-type = swap

Keep on reading!

binutils and the error ld: unrecognized option ‘–no-dynamic-linker’

Yet another bites of an old bintuils installed in the system, which leads to an error and failed a building of glibc this time. The last time it was a kernel building failure, check out here – . Most of the time, these kind of errors occurs when upgrading an old system, so as soon as building the new binutils package with emerge it is mandatory to remove the old one to minimize compiling errors of this sort.

main menu
building failure

This time the error under Gentoo system is (but it could happen in any system with old and new binutils!):

/usr/lib/gcc/x86_64-pc-linux-gnu/11/../../../../x86_64-pc-linux-gnu/bin/ld: unrecognized option '--no-dynamic-linker'
/usr/lib/gcc/x86_64-pc-linux-gnu/11/../../../../x86_64-pc-linux-gnu/bin/ld: use the --help option for usage information
collect2: error: ld returned 1 exit status

To fix the error simply remove the (all) old binutils package(s) with emerge command:

[root@srv ~]# emerge -vaC =binutils-2.25-r1
 * This action can remove important packages! In order to be safer, use
 * `emerge -pv --depclean <atom>` to check for reverse dependencies before
 * removing packages.

>>> These are the packages that would be unmerged:

 sys-devel/binutils
    selected: 2.25-r1 
   protected: none 
     omitted: 2.41-r1 

All selected packages: =sys-devel/binutils-2.25-r1

>>> 'Selected' packages are slated for removal.
>>> 'Protected' and 'omitted' packages will not be removed.

Would you like to unmerge these packages? [Yes/No] yes
>>> Waiting 5 seconds before starting...
>>> (Control-C to abort)...
>>> Unmerging in: 5 4 3 2 1
>>> Unmerging (1 of 1) sys-devel/binutils-2.25-r1...
No package files given... Grabbing a set.
<<<          obj /usr/x86_64-pc-linux-gnu/binutils-bin/2.25/strip
<<<          obj /usr/x86_64-pc-linux-gnu/binutils-bin/2.25/strings
<<<          obj /usr/x86_64-pc-linux-gnu/binutils-bin/2.25/size
<<<          obj /usr/x86_64-pc-linux-gnu/binutils-bin/2.25/readelf
......
......

Keep on reading!

Edit with systemctl edit to add restart on fail to a service – nfs-ganesha

A quick tip how to edit a service unit file under a c system like CentOS Stream 9 or Ubuntu. The best way is to edit it with the the tool “systemctl edit [service_name]”, which will trigger the default editor to open a temporary copy of the systemd unit file with the service name used with it. The default editor in the console is controlled by “EDITOR” variable and may be changed prior using the systemctl edit. After a successful manipulation of the system unit file the new one will be installed and a reload of the systemd unit files will be triggered with “systemctl daemon-reload” automatically. Indeed, it is just a text edit of a text file, which will do several actions when using “systemctl edit” command.

main menu
systemctl cat service

systemd options ro restart a service on fail are:

[Service]
Restart=on-failure
RestartSec=5s

Here, the example is to add a restart-on-fail functionality to the nfs-ganesha service (NFS service). The systemctl edit may be used for many other changes to the systemd unit file under the console and it is the easiest and proper way.

SCREENSHOT 1) Use “systemctl edit” to edit a copy of the systemd override unit file.

do not insert anything at the end of the comments or below the second red line comments – “### Lines below this comment will be discarded”. This temporary override file includes a systemd unit file of the service, which is opened for editing. The result override.conf file will only include the added lines, no other comments shown below the second red line.

main menu
systemctl edit opened

Keep on reading!

Change time zone for syslog messages in syslog-ng

When sending syslog packets to a remote server the time-zone of the current server may lead to problems because the syslog-ng program sets the time-zone with offset number according to the GMT. The remote server, especially if not a syslog-ng one, may interpret the offset as an offset to the UTC (Coordinated Universal Time), which leads times with an hour into the future.

main menu
configuration in syslog-ng

Note, this whole problem is because of the Daylight saving time and there are almost 6 months when the GMT is not equal to the UTC and it is an hour ahead. Probably it is not a good idea to offset according to the GMT, because of the Daylight saving time during the summer, but this is on the syslog-ng development side.
There is one option time-zone(“[time_zone_string]”), which allows to change the time-zone of the destination packets. To avoid misinterprets of the date and time in the message packets the best way is to use it with UTC, so the local system will do the all necessary to convert the local time to UTC properly.
The configuration below uses time-zone(“[time_zone_string]”) from the current local time to UTC, because the current local time zone is EEST (Eastern European Summer Time), which 3 hours ahead of UTC during the summer period and 2 during winter (Eastern European Time – EET).

Relay the local web server logs from the local UDP port to the remote server using reliable TCP connection and changing the local time to UTC of the packets.

#NGINX - web logs
source udp_local {
    network(ip(127.0.0.1) port(514) transport("udp") so_rcvbuf(67108864) log_fetch_limit(1000) max-connections(1000) log-iw-size(1000000));
};

filter filter_nginx_access_log { program(nginx); };
destination d_tcp_syslog {
  syslog("10.10.10.10"
         port(10514) transport("tcp") disk-buffer(mem-buf-length(10000) mem-buf-size(128M) disk-buf-size(1024M) reliable(yes) dir("/var/lib/syslog-ng"))
         time_zone("UTC")
  );
};
log { source(udp_local); filter(filter_nginx_access_log); destination(d_tcp_syslog); };
#NGINX-end

the time_zone(“UTC”) in destination rule will ensure the packets have proper time related to the local server’s time in UTC and the mistake of misinterpreted date time is unlikely on a remote server.
More articles with syslog-nghttps://ahelpme.com/tag/syslog-ng/.

Send coins in Groestlcoin network from command line with Groestlcoin Core 25 in year 2023

This article an updated version of Send coins in Groestlcoin network with Groestlcoin Core (cli), because it appeared many things handling the wallets with the command-line have changed.

main menu
groestlcoin-cli sendtoaddress

The basic notes to send and receive are:

  • a Groestlcoin address is required.
  • a Groestlcoin wallet contains Groestlcoin address
  • the Groestlcoin wallet application (i.e. Groestlcoin node, it is the same application) needs a synchronized Groestlcoin to operate properly, such as send and receive Groestlcoin coins.
  • the Groestlcoin wallet may be created, loaded or imported with the Groestlcoin tools.
  • if there is only one Groestlcoin wallet loaded it would be the default one and it would not require additional options to the Groestlcoin tool to specify, which wallet would be used for the current command.

Here are the steps needed to transfer funds under the Linux distro of Ubuntu securely. To be able to transfer money securely without any 3rd party involved (no online wallet or wallets, which is unclear which node they connect to) just funds from your personal Groestlcoin wallet address on your computer to another Groestlcoin wallet address it is needed a running Groestlcoin node using Groestlcoin Core command line tool:groestlcoin-cli – this is command line tool for managing the Groestlcoin wallets.

STEP 1) Install and run a Groestlcoin node with groestlcoind

The first step is to start a Groestlcoin node by following this updated article – Building from source and run a Groestlcoin node (cli only) under Ubuntu 22.04 LTS. It will help the user to build from the official source code the Groestlcoin Core software, which will include the Groestlcoin node and wallet functionalities. All of the file paths and application names are real and correct if the above article was used.
It’s worth mentioning, that the Groestlcoin node must be running and synced with the Groestlcoin network. Here is how to check it:

myuser@mydesktop:~/groestlcoin-core/bin$ ./groestlcoin-cli getblockchaininfo
{
  "chain": "main",
  "blocks": 4734023,
  "headers": 4734023,
  "bestblockhash": "00000000000020d22b156e27af600fcdc3fd315f8896bbdb5ab748260fbfa3dd",
  "difficulty": 457347.0794165397,
  "time": 1693300370,
  "mediantime": 1693300091,
  "verificationprogress": 0.9999998125955512,
  "initialblockdownload": false,
  "chainwork": "00000000000000000000000000000000000000000000016eeb7afc66a3b219fb",
  "size_on_disk": 3040987475,
  "pruned": false,
  "warnings": ""
}

Keep on reading!

Build and run the Groestlcoin Core 25.0 node with a graphical wallet

In continuation to the article Building from source and run a Groestlcoin node (cli only) under Ubuntu 22.04 LTS, which offers only a command line management to the Groestlcoin wallets, this article will show a more convenient way with a graphical user interface. Groistlcoin Core software includes a graphical user interface for the Groestlcoin wallet.

main menu
node window synced with network

The first thing is to build the Groestlcoin Core software as shown in the link above with some additional dependencies and options.
It’s worth noting there is a package for the graphical Groestlcoin wallet on the official site of Groestlcoin, but the idea behind this series of articles is to build everything from the official source code and to run an own Groestlcoin node, which will be used for the user’s Groestlcoin wallet. Such no trusting anyone or any site, but only the official source code of the project. The security is really important in the crypto world.

Here are the steps to build and run the Groestlcoin node with wallet functionality – command line and graphical user interface. The graphical user interface uses QT5 to build the wallet interface and all libraries are included in the official Ubuntu repositories.

STEP 1) Build and run the Groestlcoin node

For more detailed information check out Building from source and run a Groestlcoin node (cli only) under Ubuntu 22.04 LTS.

First, install the dependencies but with additional libraries including the QT5 and qrencode. Update the system and install the needed additional binaries and libraries to build and run the Groestlcoin core package. These dependencies include the ones needed to build the Groestcoin wallet functionality with GUI! By default, many Linux systems won’t even include dependencies needed to build the wallet.

sudo apt -y update
sudo apt -y upgrade
sudo apt install build-essential libssl-dev libboost-all-dev libtool automake libevent-dev bsdmainutils git make g++ gcc autoconf cpp ngrep iftop sysstat autotools-dev pkg-config libminiupnpc-dev libzmq3-dev libdb-dev libdb5.3++-dev sqlite3 libsqlite3-dev

An additional 1042 Mbytes will be occupied.
Keep on reading!

Generate a new Groestlcoin address (wallet) and list wallets and addresses using command line cli verson 25.0.0

This article an updated version of Generate a new Groestlcoin address (wallet) and list accounts and addresses, because it appeared many things handling the wallets and address with the command-line have changed.

main menu
new wallet and address

The generation of a new Groestlcoin address is relatively simple, just use the command line tool – groestlcoin-cli, which is a Groestlcoin Core RPC client talking to the Groestlcoin node. So a working and synchronized Groestlcoin node is needed. Check out Building from source and run a Groestlcoin node (cli only) under Ubuntu 22.04 LTS for more information how to build and run a Groestlcoin node.

DO NOT TRUST any online website or any other Internet source to generate your Groestlcoin wallet address for you. DO IT YOURSELF with the official software from the official site!
If the user followed the above link to build and run a Groestlcoin and has waited to synchronize, it is time to use the groestlcoin-cli to create a wallet and then generate addresses. In fact, the wallet contains Groestlcoin addresses and it may be encrypted for better security. The Groestlcoin node is running and synchronized.

STEP 1) Create a new or load an old Groestlcoin wallet.

There is no default wallet and no wallet is loaded automatically on start, by default (indeed a wallet may be automatically loaded, but it should be specified on loading).
List all the Groestlcoin wallets under the current user:

myuser@mydesktop:~$ cd groestlcoin-core/bin/
myuser@mydesktop:~/groestlcoin-core/bin$ ./groestlcoin-cli listwallets
[
]
myuser@mydesktop:~/groestlcoin-core/bin$ ./groestlcoin-cli listwalletdir
{
  "wallets": [
  ]
}
myuser@mydesktop:~/groestlcoin-core/bin$ ./groestlcoin-cli listaddressgroupings
error code: -18
error message:
No wallet is loaded. Load a wallet using loadwallet or create a new one with createwallet. (Note: A default wallet is no longer automatically created)

Apparently, there are no wallets, so here is how to create a wallet:
Create a wallet with:

myuser@mydesktop:~/groestlcoin-core/bin$ ./groestlcoin-cli createwallet my-groestlcoin-wallet
{
  "name": "my-groestlcoin-wallet"
}
myuser@mydesktop:~/groestlcoin-core/bin$ ./groestlcoin-cli encryptwallet 'joo8laeW9Chietae&phu'
wallet encrypted; The keypool has been flushed and a new HD seed was generated (if you are using HD). You need to make a new backup.

When creating one wallet, it will become the default one, and all commands on groestlcoin-cli will use it. To specify exactly the name of the wallet with the command, the option “-rpcwallet=” should be used. In general, with one wallet there is no need to specify the wallet name, but when there are two or more loaded wallets, it is mandatory to specify with “-rpcwallet=” the wallet name.
Creating one more wallet with groestlcoin-cli will result in two loaded wallets, so after that, all commands should include “-rpcwallet=”.

myuser@mydesktop:~/groestlcoin-core/bin$ ./groestlcoin-cli createwallet my-groestlcoin-wallet-2
{
  "name": "my-groestlcoin-wallet-2"
}
myuser@mydesktop:~/groestlcoin-core/bin$ ./groestlcoin-cli -rpcwallet="my-groestlcoin-wallet-2" encryptwallet "ief0ahshao8ca8Dai-ng"
wallet encrypted; The keypool has been flushed and a new HD seed was generated (if you are using HD). You need to make a new backup.

Keep on reading!

QEMU full virtualization – CPU emulations (enable/disable CPU flags/instruction sets) of QEMU 8.0

Yet another update to this QEMU series after the versions 2.0.0QEMU full virtualization – CPU emulations (enable/disable CPU flags/instruction sets) of QEMU 2.0.0 and version 6.2QEMU full virtualization – CPU emulations (enable/disable CPU flags/instruction sets) of QEMU 6.2.0

main menu
hot add CPU

The latest version of QEMU is 8.0.4 and it offers way more CPU flags and features! You can use QEMU with nearly native full virtualization. Here are some important tips for the guest CPU to consider when using QEMU directly (without any virtualization manager like virt-manager, libvirt and so on).

TIP 1) CPU emulation of x86

You can see what options are available for host emulation with:

root@srv ~ # qemu-system-x86_64 -cpu help
Available CPUs:
x86 486                   (alias configured by machine type)
x86 486-v1                
x86 Broadwell             (alias configured by machine type)
x86 Broadwell-IBRS        (alias of Broadwell-v3)
x86 Broadwell-noTSX       (alias of Broadwell-v2)
x86 Broadwell-noTSX-IBRS  (alias of Broadwell-v4)
x86 Broadwell-v1          Intel Core Processor (Broadwell)
x86 Broadwell-v2          Intel Core Processor (Broadwell, no TSX)
x86 Broadwell-v3          Intel Core Processor (Broadwell, IBRS)
x86 Broadwell-v4          Intel Core Processor (Broadwell, no TSX, IBRS)
x86 Cascadelake-Server    (alias configured by machine type)
x86 Cascadelake-Server-noTSX  (alias of Cascadelake-Server-v3)
x86 Cascadelake-Server-v1  Intel Xeon Processor (Cascadelake)
x86 Cascadelake-Server-v2  Intel Xeon Processor (Cascadelake) [ARCH_CAPABILITIES]
x86 Cascadelake-Server-v3  Intel Xeon Processor (Cascadelake) [ARCH_CAPABILITIES, no TSX]
x86 Cascadelake-Server-v4  Intel Xeon Processor (Cascadelake) [ARCH_CAPABILITIES, no TSX]
x86 Cascadelake-Server-v5  Intel Xeon Processor (Cascadelake) [ARCH_CAPABILITIES, EPT switching, XSAVES, no TSX]
x86 Conroe                (alias configured by machine type)
x86 Conroe-v1             Intel Celeron_4x0 (Conroe/Merom Class Core 2)
x86 Cooperlake            (alias configured by machine type)
x86 Cooperlake-v1         Intel Xeon Processor (Cooperlake)
x86 Cooperlake-v2         Intel Xeon Processor (Cooperlake) [XSAVES]
x86 Denverton             (alias configured by machine type)
x86 Denverton-v1          Intel Atom Processor (Denverton)
x86 Denverton-v2          Intel Atom Processor (Denverton) [no MPX, no MONITOR]
x86 Denverton-v3          Intel Atom Processor (Denverton) [XSAVES, no MPX, no MONITOR]
x86 Dhyana                (alias configured by machine type)
x86 Dhyana-v1             Hygon Dhyana Processor
x86 Dhyana-v2             Hygon Dhyana Processor [XSAVES]
x86 EPYC                  (alias configured by machine type)
x86 EPYC-IBPB             (alias of EPYC-v2)
x86 EPYC-Milan            (alias configured by machine type)
x86 EPYC-Milan-v1         AMD EPYC-Milan Processor
x86 EPYC-Rome             (alias configured by machine type)
x86 EPYC-Rome-v1          AMD EPYC-Rome Processor
x86 EPYC-Rome-v2          AMD EPYC-Rome Processor
x86 EPYC-v1               AMD EPYC Processor
x86 EPYC-v2               AMD EPYC Processor (with IBPB)
x86 EPYC-v3               AMD EPYC Processor
x86 Haswell               (alias configured by machine type)
x86 Haswell-IBRS          (alias of Haswell-v3)
x86 Haswell-noTSX         (alias of Haswell-v2)
x86 Haswell-noTSX-IBRS    (alias of Haswell-v4)
x86 Haswell-v1            Intel Core Processor (Haswell)
x86 Haswell-v2            Intel Core Processor (Haswell, no TSX)
x86 Haswell-v3            Intel Core Processor (Haswell, IBRS)
x86 Haswell-v4            Intel Core Processor (Haswell, no TSX, IBRS)
x86 Icelake-Server        (alias configured by machine type)
x86 Icelake-Server-noTSX  (alias of Icelake-Server-v2)
x86 Icelake-Server-v1     Intel Xeon Processor (Icelake)
x86 Icelake-Server-v2     Intel Xeon Processor (Icelake) [no TSX]
x86 Icelake-Server-v3     Intel Xeon Processor (Icelake)
x86 Icelake-Server-v4     Intel Xeon Processor (Icelake)
x86 Icelake-Server-v5     Intel Xeon Processor (Icelake) [XSAVES]
x86 Icelake-Server-v6     Intel Xeon Processor (Icelake) [5-level EPT]
x86 IvyBridge             (alias configured by machine type)
x86 IvyBridge-IBRS        (alias of IvyBridge-v2)
x86 IvyBridge-v1          Intel Xeon E3-12xx v2 (Ivy Bridge)
x86 IvyBridge-v2          Intel Xeon E3-12xx v2 (Ivy Bridge, IBRS)
x86 KnightsMill           (alias configured by machine type)
x86 KnightsMill-v1        Intel Xeon Phi Processor (Knights Mill)
x86 Nehalem               (alias configured by machine type)
x86 Nehalem-IBRS          (alias of Nehalem-v2)
x86 Nehalem-v1            Intel Core i7 9xx (Nehalem Class Core i7)
x86 Nehalem-v2            Intel Core i7 9xx (Nehalem Core i7, IBRS update)
x86 Opteron_G1            (alias configured by machine type)
x86 Opteron_G1-v1         AMD Opteron 240 (Gen 1 Class Opteron)
x86 Opteron_G2            (alias configured by machine type)
x86 Opteron_G2-v1         AMD Opteron 22xx (Gen 2 Class Opteron)
x86 Opteron_G3            (alias configured by machine type)
x86 Opteron_G3-v1         AMD Opteron 23xx (Gen 3 Class Opteron)
x86 Opteron_G4            (alias configured by machine type)
x86 Opteron_G4-v1         AMD Opteron 62xx class CPU
x86 Opteron_G5            (alias configured by machine type)
x86 Opteron_G5-v1         AMD Opteron 63xx class CPU
x86 Penryn                (alias configured by machine type)
x86 Penryn-v1             Intel Core 2 Duo P9xxx (Penryn Class Core 2)
x86 SandyBridge           (alias configured by machine type)
x86 SandyBridge-IBRS      (alias of SandyBridge-v2)
x86 SandyBridge-v1        Intel Xeon E312xx (Sandy Bridge)
x86 SandyBridge-v2        Intel Xeon E312xx (Sandy Bridge, IBRS update)
x86 SapphireRapids        (alias configured by machine type)
x86 SapphireRapids-v1     Intel Xeon Processor (SapphireRapids)
x86 Skylake-Client        (alias configured by machine type)
x86 Skylake-Client-IBRS   (alias of Skylake-Client-v2)
x86 Skylake-Client-noTSX-IBRS  (alias of Skylake-Client-v3)
x86 Skylake-Client-v1     Intel Core Processor (Skylake)
x86 Skylake-Client-v2     Intel Core Processor (Skylake, IBRS)
x86 Skylake-Client-v3     Intel Core Processor (Skylake, IBRS, no TSX)
x86 Skylake-Client-v4     Intel Core Processor (Skylake, IBRS, no TSX) [IBRS, XSAVES, no TSX]
x86 Skylake-Server        (alias configured by machine type)
x86 Skylake-Server-IBRS   (alias of Skylake-Server-v2)
x86 Skylake-Server-noTSX-IBRS  (alias of Skylake-Server-v3)
x86 Skylake-Server-v1     Intel Xeon Processor (Skylake)
x86 Skylake-Server-v2     Intel Xeon Processor (Skylake, IBRS)
x86 Skylake-Server-v3     Intel Xeon Processor (Skylake, IBRS, no TSX)
x86 Skylake-Server-v4     Intel Xeon Processor (Skylake, IBRS, no TSX)
x86 Skylake-Server-v5     Intel Xeon Processor (Skylake, IBRS, no TSX) [IBRS, XSAVES, EPT switching, no TSX]
x86 Snowridge             (alias configured by machine type)
x86 Snowridge-v1          Intel Atom Processor (SnowRidge)
x86 Snowridge-v2          Intel Atom Processor (Snowridge, no MPX)
x86 Snowridge-v3          Intel Atom Processor (Snowridge, no MPX) [XSAVES, no MPX]
x86 Snowridge-v4          Intel Atom Processor (Snowridge, no MPX) [no split lock detect, no core-capability]
x86 Westmere              (alias configured by machine type)
x86 Westmere-IBRS         (alias of Westmere-v2)
x86 Westmere-v1           Westmere E56xx/L56xx/X56xx (Nehalem-C)
x86 Westmere-v2           Westmere E56xx/L56xx/X56xx (IBRS update)
x86 athlon                (alias configured by machine type)
x86 athlon-v1             QEMU Virtual CPU version 2.5+
x86 core2duo              (alias configured by machine type)
x86 core2duo-v1           Intel(R) Core(TM)2 Duo CPU     T7700  @ 2.40GHz
x86 coreduo               (alias configured by machine type)
x86 coreduo-v1            Genuine Intel(R) CPU           T2600  @ 2.16GHz
x86 kvm32                 (alias configured by machine type)
x86 kvm32-v1              Common 32-bit KVM processor
x86 kvm64                 (alias configured by machine type)
x86 kvm64-v1              Common KVM processor
x86 n270                  (alias configured by machine type)
x86 n270-v1               Intel(R) Atom(TM) CPU N270   @ 1.60GHz
x86 pentium               (alias configured by machine type)
x86 pentium-v1            
x86 pentium2              (alias configured by machine type)
x86 pentium2-v1           
x86 pentium3              (alias configured by machine type)
x86 pentium3-v1           
x86 phenom                (alias configured by machine type)
x86 phenom-v1             AMD Phenom(tm) 9550 Quad-Core Processor
x86 qemu32                (alias configured by machine type)
x86 qemu32-v1             QEMU Virtual CPU version 2.5+
x86 qemu64                (alias configured by machine type)
x86 qemu64-v1             QEMU Virtual CPU version 2.5+
x86 base                  base CPU model type with no features enabled
x86 host                  processor with all supported host features 
x86 max                   Enables all features supported by the accelerator in the current host

Recognized CPUID flags:
  3dnow 3dnowext 3dnowprefetch abm ace2 ace2-en acpi adx aes amd-no-ssb
  amd-ssbd amd-stibp amx-bf16 amx-int8 amx-tile apic arat arch-capabilities
  arch-lbr avic avx avx-vnni avx2 avx512-4fmaps avx512-4vnniw avx512-bf16
  avx512-fp16 avx512-vp2intersect avx512-vpopcntdq avx512bitalg avx512bw
  avx512cd avx512dq avx512er avx512f avx512ifma avx512pf avx512vbmi
  avx512vbmi2 avx512vl avx512vnni bmi1 bmi2 bus-lock-detect cid cldemote
  clflush clflushopt clwb clzero cmov cmp-legacy core-capability cr8legacy
  cx16 cx8 dca de decodeassists ds ds-cpl dtes64 erms est extapic f16c
  flushbyasid fma fma4 fpu fsgsbase fsrc fsrm fsrs full-width-write fxsr
  fxsr-opt fzrm gfni hle ht hypervisor ia64 ibpb ibrs ibrs-all ibs intel-pt
  intel-pt-lip invpcid invtsc kvm-asyncpf kvm-asyncpf-int
  kvm-hint-dedicated kvm-mmu kvm-msi-ext-dest-id kvm-nopiodelay
  kvm-poll-control kvm-pv-eoi kvm-pv-ipi kvm-pv-sched-yield
  kvm-pv-tlb-flush kvm-pv-unhalt kvm-steal-time kvmclock kvmclock
  kvmclock-stable-bit la57 lahf-lm lbrv lm lwp mca mce md-clear mds-no
  misalignsse mmx mmxext monitor movbe movdir64b movdiri mpx msr mtrr
  nodeid-msr npt nrip-save nx osvw pae pat pause-filter pbe pcid pclmulqdq
  pcommit pdcm pdpe1gb perfctr-core perfctr-nb pfthreshold pge phe phe-en
  pks pku pmm pmm-en pn pni popcnt pschange-mc-no pse pse36 rdctl-no rdpid
  rdrand rdseed rdtscp rsba rtm sep serialize sgx sgx-aex-notify sgx-debug
  sgx-edeccssa sgx-exinfo sgx-kss sgx-mode64 sgx-provisionkey sgx-tokenkey
  sgx1 sgx2 sgxlc sha-ni skinit skip-l1dfl-vmentry smap smep smx spec-ctrl
  split-lock-detect ss ssb-no ssbd sse sse2 sse4.1 sse4.2 sse4a ssse3 stibp
  svm svm-lock svme-addr-chk syscall taa-no tbm tce tm tm2 topoext tsc
  tsc-adjust tsc-deadline tsc-scale tsx-ctrl tsx-ldtrk umip v-vmsave-vmload
  vaes vgif virt-ssbd vmcb-clean vme vmx vmx-activity-hlt
  vmx-activity-shutdown vmx-activity-wait-sipi vmx-apicv-register
  vmx-apicv-vid vmx-apicv-x2apic vmx-apicv-xapic vmx-cr3-load-noexit
  vmx-cr3-store-noexit vmx-cr8-load-exit vmx-cr8-store-exit vmx-desc-exit
  vmx-encls-exit vmx-entry-ia32e-mode vmx-entry-load-bndcfgs
  vmx-entry-load-efer vmx-entry-load-pat vmx-entry-load-perf-global-ctrl
  vmx-entry-load-pkrs vmx-entry-load-rtit-ctl vmx-entry-noload-debugctl
  vmx-ept vmx-ept-1gb vmx-ept-2mb vmx-ept-advanced-exitinfo
  vmx-ept-execonly vmx-eptad vmx-eptp-switching vmx-exit-ack-intr
  vmx-exit-clear-bndcfgs vmx-exit-clear-rtit-ctl vmx-exit-load-efer
  vmx-exit-load-pat vmx-exit-load-perf-global-ctrl vmx-exit-load-pkrs
  vmx-exit-nosave-debugctl vmx-exit-save-efer vmx-exit-save-pat
  vmx-exit-save-preemption-timer vmx-flexpriority vmx-hlt-exit vmx-ins-outs
  vmx-intr-exit vmx-invept vmx-invept-all-context vmx-invept-single-context
  vmx-invept-single-context vmx-invept-single-context-noglobals
  vmx-invlpg-exit vmx-invpcid-exit vmx-invvpid vmx-invvpid-all-context
  vmx-invvpid-single-addr vmx-io-bitmap vmx-io-exit vmx-monitor-exit
  vmx-movdr-exit vmx-msr-bitmap vmx-mtf vmx-mwait-exit vmx-nmi-exit
  vmx-page-walk-4 vmx-page-walk-5 vmx-pause-exit vmx-ple vmx-pml
  vmx-posted-intr vmx-preemption-timer vmx-rdpmc-exit vmx-rdrand-exit
  vmx-rdseed-exit vmx-rdtsc-exit vmx-rdtscp-exit vmx-secondary-ctls
  vmx-shadow-vmcs vmx-store-lma vmx-true-ctls vmx-tsc-offset
  vmx-tsc-scaling vmx-unrestricted-guest vmx-vintr-pending vmx-vmfunc
  vmx-vmwrite-vmexit-fields vmx-vnmi vmx-vnmi-pending vmx-vpid
  vmx-wbinvd-exit vmx-xsaves vmx-zero-len-inject vpclmulqdq waitpkg
  wbnoinvd wdt x2apic xcrypt xcrypt-en xfd xgetbv1 xop xsave xsavec
  xsaveerptr xsaveopt xsaves xstore xstore-en xtpr

Keep on reading!

Building from source and run a Groestlcoin node (cli only) under Ubuntu 22.04 LTS

It was a bit while after the Building from source a Groestlcoin node (cli only) under Ubuntu 16 LTS. So after 6 years is it the same procedure or there are additional or simplified steps (to build) and run a cryptocurrency Groestlcoin node? The GRS price seems the same as it was 6 years ago, but there are some new things in the software.

main menu
groestlcoin-cli getblockchaininfo

The first step is to build the software and it is one of the most important steps – download the source code ONLY from the official source, check the official site https://www.groestlcoin.org/groestlcoin-core-wallet/ where the source code could be downloaded or to see where is the official place for the source code – https://github.com/Groestlcoin/groestlcoin. Check the links yourself! The https://github.com/Groestlcoin/groestlcoin git link will be used to download the latest stable version of the code and to build a Groestlcoin node, which may or may not include wallet capabilities. Building the Groestlcoin core package from the source you’ll have your private and secure Groestlcoin node (and wallet), which could be used to make secure transactions and receive funds in the Groestlcoin network and a lot more! DO IT YOURSELF – the most secure way of generating a Groestlcoin wallet address, making transactions such as sending and receiving coins, and storing your wallets.

STEP 1) Update your system and install dependencies

Update your system and install the needed additional binaries and libraries to build and run the Groestlcoin core package. These dependencies include the ones needed to build the Groestcoin wallet functionality! By default, many Linux systems won’t include dependencies needed to build the wallet.

main menu
sudo apt install groestlcoin dependencies

sudo apt -y update
sudo apt -y upgrade
sudo apt install build-essential libssl-dev libboost-all-dev libtool automake libevent-dev bsdmainutils git make g++ gcc autoconf cpp ngrep iftop sysstat autotools-dev pkg-config libminiupnpc-dev libzmq3-dev libdb-dev libdb5.3++-dev sqlite3 libsqlite3-dev

An additional 722 Mbytes will be occupied.
Keep on reading!

Review of freshly installed Fedora 38 Xfce Desktop

After the tutorial on how to install Fedora 38 Xfce Desktop this tutorial is mainly to see what to expect from a freshly installed Fedora 36 Xfce Desktop – the look and feel of the new Xfce GUI (Xfce version – 4.18). The Fedora 38 Xfce Desktop is part of Fedora spins – https://spins.fedoraproject.org/xfce/
Here you can find out how to install it – Install Fedora 38 Xfce Desktop.
The idea of this article is to see what to expect from Fedora 38 Xfce – the look and feel of the GUI, the default installed programs, and their look and how to do some basic steps with them. Here you’ll find more than 170 screenshots and not so many texts we do not want to turn this review of many texts and version information and 3 meaningless screenshots, which you could not see anything for the user interface because these days it is the primary goal of a Desktop system. You can expect more of this kind of review in the future.
This article is the first part of reviewing the Fedora 36 Xfce Desktop. The second article contains Xfce Settings screenshots that are coming soon.

Xfce is a collection of programs that provides a features-rich desktop environment.

Here are some core elements:

  • Window Manager (xfwm4) – Handles the placement of windows on the screen.
  • Panel (xfce4-panel) – Provides a home for window buttons, launchers, app menu and more.
  • Desktop Manager (xfdesktop) – Sets desktop backgrounds, handles icons and more.
  • File Manager (thunar) – Manages your files in a modern, easy-to-use and fast way.
  • Volume Manager (thunar-volman) – Manages removable drives and media for Thunar.
  • Session Manager (xfce4-session) – Saves and restores your session, handles startup, autostart and shutdown.
  • Setting System (xfce4-settings) – Configures appearance, display, keyboard, and mouse settings.
  • Application Finder (xfce4-appfinder) – Quickly finds and launches applications installed on your system
  • Settings Daemon (xfconf) – Stores your settings in a D-Bus-based configuration system.
  • A Menu Library (garcon) – Implements a freedesktp.org compliant menu based on GLib and GIO.
  • Thumbnails Services (tumbler) – Implements the thumbnails management D-Bus specification.

Fedora 38 Xfce screenshots

SCREENSHOT 1) Fedora (6.2.9-300.fc38.x86_64) 38 (Xfce)

main menu
grub 2 entry boot

Keep on reading!