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      How to instruct consul to disable automatic checking for updates

      pubsub.slavino.sk / sleeplessbestie · Friday, 30 September, 2022 - 11:00 edit

    Instruct consul to disable automatic checking for updates. I am using Consul inside an isolated network, so it cannot connect to the world. $ journalctl -u consul -f [...] Jul 17 18:55:15 jammy consul[3363]: 2022-07-17T18:55:15.044Z [ERROR] agent: Failed to check for updates: error="Get "https://checkpoint-api.hashicorp.com/v1/check/consul?arch=amd64&os=linux&signature=0912e301-5a4e-e51d-b24a-b2a9a7373da5&version=1.12.3": dial tcp: lookup checkpoint-api.hashicorp.com on [::1]:53: read udp [::1]:35291->[::1]:53: read: connection […]

    Značky: #Consul, #Linux, #SysOps

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      How to configure Unbound DNS validating resolver

      pubsub.slavino.sk / sleeplessbestie · Wednesday, 28 September, 2022 - 11:00 edit

    Configure Unbound DNS validating resolver. Determine device address. $ ip --brief address show eth0 eth0 UP 172.16.151.254/21 Update package index. $ apt update Upgrade packages. $ apt upgrade Install Dynamic Firewall Manager. $ sudo apt install firewalld Inspect initial setting for public zone. $ sudo firewall-cmd --list-all --zone public public target: default icmp-block-inversion: no interfaces: […]

    Značky: #Linux, #Raspberry, #SysOps

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      How to display currently connected wireless network

      pubsub.slavino.sk / sleeplessbestie · Saturday, 24 September, 2022 - 11:00 edit

    Display the name of the wireless network you are connected to. iwgetid Use iwgetid utility to display currently connected wireless network. $ iwgetid wlan0 ESSID:"Searching..." Display the name of the wireless network you are connected to using specific wireless device. $ iwgetid --raw wlan0 Searching... wpa_cli Use WPA command-line client to inspect available interfaces. $ […]

    Značky: #Raspberry, #Linux, #SysOps

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      How to configure Consul Access Control Lists

      pubsub.slavino.sk / sleeplessbestie · Friday, 23 September, 2022 - 11:00 edit

    Configure Consul Access Control Lists. Inspect current server configuration. $ sudo -u consul cat /etc/consul.d/consul.hcl # datacenter datacenter = "dc-lab-1" # data directory data_dir = "/opt/consul" # server mode server = true # bind address bind_addr = "0.0.0.0" # single-node server bootstrap = true # number of expected servers in the datacenter #bootstrap_expect = 3 […]

    Značky: #Linux, #SysOps, #Consul

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      How to parse and filter dpkg database

      pubsub.slavino.sk / sleeplessbestie · Wednesday, 21 September, 2022 - 11:00 edit

    Parse and filter dpkg database to display selected fields or other specific information. Install Gawk script to parse dpkg databases. $ sudo apt install dpkg-awk Display package information. $ dpkg-awk "package:^vim$" Package: vim Status: install ok installed Priority: optional Section: editors Installed-Size: 3615 Maintainer: Ubuntu Developers <ubuntu-devel-discuss@lists.ubuntu.com> Architecture: amd64 Version: 2:8.2.2434-3ubuntu3.1 Provides: editor Depends: vim-common […]

    Značky: #SysOps, #Linux, #Ubuntu

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      How to scan wireless networks

      pubsub.slavino.sk / sleeplessbestie · Thursday, 15 September, 2022 - 11:00 edit

    Scan wireless networks. Use iwlist utility to scan wireless networks. $ sudo iwlist wlan0 scanning wlan0 Scan completed : Cell 01 - Address: 00:78:CD:91:BA:30 Channel:6 Frequency:2.437 GHz (Channel 6) Quality=70/70 Signal level=-20 dBm Encryption key:on ESSID:"Searching..." Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 6 Mb/s 9 Mb/s; 12 Mb/s; 18 Mb/s Bit Rates:24 […]

    Značky: #Raspberry, #SysOps, #Linux

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      How to access service socket as a regular user

      pubsub.slavino.sk / sleeplessbestie · Wednesday, 14 September, 2022 - 11:00 edit

    Create an exception for a regular user to access service socket using systemd. I will use HAProxy to show the standard group based technique and the systemd/ACLs approach. Prerequisites Create a dedicated user and group that will be used in this example. $ sudo groupadd --gid 2000 milosz $ sudo useradd --uid 2000 --gid 2000 […]

    Značky: #Bullseye, #HAProxy, #SysOps, #Linux, #systemd, #Debian

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      How to secure Consul communication

      pubsub.slavino.sk / sleeplessbestie · Friday, 9 September, 2022 - 11:00 edit

    Secure Consul communication. Generate encryption key Generate encryption key that will be used to encrypt gossip protocol. $ consul keygen wZHOCKakzCeAesu7HK07tqmc3PwJojN/jNfbXEDqplI= Generate certificates Create ssl directory. $ sudo install --directory --group consul --owner consul --mode 700 /opt/consul/ssl Create CA. $ consul tls ca create ==> Saved consul-agent-ca.pem ==> Saved consul-agent-ca-key.pem $ cat consul-agent-ca.pem -----BEGIN CERTIFICATE----- […]

    Značky: #Linux, #Consul, #SysOps

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      How to determine maximum memory capacity

      pubsub.slavino.sk / sleeplessbestie · Wednesday, 7 September, 2022 - 11:00 edit

    Determine maximum memory capacity. Use a dmidecode utility to decode SMBIOS table contents related to the memory and display using a human-readable format. $ sudo dmidecode --type memory # dmidecode 3.2 Getting SMBIOS data from sysfs. SMBIOS 2.7 present. Handle 0x003E, DMI type 16, 23 bytes Physical Memory Array Location: System Board Or Motherboard Use: […]

    Značky: #Linux, #Hardware, #SysOps