open-menu closeme
Home
Links icon
LinkedIn
About
English
github linkedin
  • IPtables - SSH in only

    calendar Sep 6, 2022 · 1 min read · iptables linux  ·
    Share on: twitter facebook linkedin copy

    I came a cross this neat little script to lock down IPtables to allow ONLY SSH in, block everything else 1#!/bin/bash 2# Flushing all rules 3iptables -F 4iptables -X 5# Setting default filter policy 6iptables -P INPUT DROP 7iptables -P OUTPUT ACCEPT 8iptables -P FORWARD DROP 9# Allow unlimited traffic on loopback …


    Read More
  • OpenSSL quick commands

    calendar Aug 26, 2022 · 1 min read · ssl linux  ·
    Share on: twitter facebook linkedin copy

    Get info about a web server cert openssl s_client -showcerts -connect registry.nexgen-poc.lan:5010 </dev/null Validate a crt against a CA crt openssl verify -CAfile rootCA.crt registry.nexgen-poc.lan.crt Thanks @Deep for spotting the error!


    Read More
  • Scrub all local disks

    calendar Aug 15, 2022 · 1 min read · bash linux  ·
    Share on: twitter facebook linkedin copy

    I was writing a script to scrub a server prior to decommissioning, something simple that would just make the disks unusbale enough that someone couldnt boot the OS or easily read the data. This is by no stretch a comprehensive disk wipe, if someone is lookign to recover data from these disks what were are doing here is …


    Read More
  • Use grep to view a file without comments

    calendar Aug 6, 2022 · 1 min read · bash linux  ·
    Share on: twitter facebook linkedin copy

    To view the contents of a fiule but remove comments and new lines you can use this excellent little command. It will remove all lines that start with # or a new line, this is particulaly useful for viewing a config file that has 99% comments and a handful of actual values(E.G OpenStack config files) grep -v -e …


    Read More
  • PCI Passthrough error 'group x is not viable' 2

    calendar Aug 5, 2022 · 2 min read · bash linux openstack pci nvidia  ·
    Share on: twitter facebook linkedin copy

    1#!/bin/bash 2# change the 999 if needed 3shopt -s nullglob 4for d in /sys/kernel/iommu_groups/{0..999}/devices/*; do 5n=${d#*/iommu_groups/*}; n=${n%%/*} 6printf 'IOMMU Group %s ' "$n" 7lspci -nns "${d##*/}" 8done; 1 2 3 4 5 6 7 8 9 10 11 12 sudo lspci -nnv | grep "c1:00.1" -i -A30 …


    Read More
  • tcpdump HTTP traffic

    calendar Aug 3, 2022 · 1 min read · bash linux  ·
    Share on: twitter facebook linkedin copy

    If you want to diagnose HTTP traffic it's sometime usefull to use tcpfump to dump the packets either on the console or to a tile Here is a nice litte command I found to run a dump of all http traffic on a defined port tcpdump -A -s 0 'src 10.10.110.254 and tcp port 5000 and (((ip[2:2] - ((ip[0]&0xf)<<2)) - …


    Read More
  • List all local linux disks

    calendar Aug 1, 2022 · 1 min read · bash linux  ·
    Share on: twitter facebook linkedin copy

    I was writing a script to interact with all local disks and i needed a simplied list of local disks, not partitions and not the loopback mounts..This is what I came up with lsblk -d | cut -f 1 -d" " | tail -n +2 | grep -v loop Which will give you a nice parseable output something like this 1sda 2sdb 3nvme0n1 …


    Read More
  • MaaS CLI

    calendar Jul 13, 2022 · 1 min read · maas linux  ·
    Share on: twitter facebook linkedin copy

    The MaaS CLI documentation is a bit trash Login to MaaS maas login admin http://10.10.110.250:5240/MAAS/api/2.0/ 5HvxATpW5487XmkSjZ:CXfC3McdvV9U9aefbp:wB9jGT8AJ4DUYArJ8dDqeRVczBwJEXMk Set the IPMI Cipher Suite ID to 'freeipmi-tools default' maas admin machine update bfyq3e power_parameters_cipher_suite_id='' Commission …


    Read More
  • Network monitoring tools

    calendar Oct 21, 2020 · 1 min read · linux networking  ·
    Share on: twitter facebook linkedin copy

    bmon Nethogs Glances Warning dependency heavy


    Read More
  • Moutning a CephFS share using ceph-fuse

    calendar May 16, 2020 · 1 min read · linux ceph  ·
    Share on: twitter facebook linkedin copy

    I always forget how to mount the subfolder of a CephFS filesystem sudo ceph-fuse -m 192.168.2.9:6789 -r /subfolder /folder/on/my/machine Note: The proceeding / after the -r is important Some great info here on restricting access to specific folders and more notes on mounting …


    Read More
    • ««
    • «
    • 1
    • 2
    • 3
    • 4
    • »
    • »»

Cory Hawkvelt photo

Cory Hawkvelt

CTO @ Nexgen Cloud | Career Nerd and Open Source Cloud Architect
Read More

Recent Posts

  • Deploying pam_ussh: A Comprehensive Guide
  • Unpacking the NVIDIA H100 Tensor Core GPU: A Deep Dive for CTOs
  • Caddy proxy for OpenStack API's
  • HP Server ACPI errors
  • vxlan: non-ECT from 10.254.8.23 with TOS=0x2
  • Install Ceph by hand Ubuntu 22.04
  • Gnocchi Convert Temperature F to C
  • Install HP SSACLI HPACUCLI tool on Ubuntu 20.04

Tags

LINUX 32 CEPH 24 BASH 22 OPENSTACK 13 NETWORKING 10 DOCKER 8 CONFIG 6 HP 5 HPACUCLI 5 OPENSTACK-QUEENS 5 QEMU 5 SSH 5 TROUBLESHOOTING 5 CENTOS7 4
All Tags
ACTIVE-BACKUP1 ADB1 AI1 ANDROID1 ANSIBLE2 APT1 AUTODISCOVER1 BACKUP1 BASH22 BIND1 BLUETOOTH1 CACHE1 CADDY1 CAS1 CENTOS74 CEPH24 CEPH-NAUTILUS1 CERTIFICATES1 CINDER3 COLLECTD1 COMWARE1 CONFIG6 CRYPTOLOCK1 CRYPTOMINER2 DATABASE1 DELL1 DELL-S600-ON1 DELLMD3060JBOD1 DHCP1 DISK-MGMT1 DNS1 DOCKER8 DRIVERS1 ESP826621 ESPTOOL1 FAIL2BAN1 FEDORA261 FIBRECHANNEL1 FIRMWARE1 FREEOTP1 FTOS1 GIT1 GNOCCHI3 GO1 GPU1 H1001 HAPROXY2 HARDWARE2 HORIZON1 HP5 HP-ILO1 HPACUCLI5 HPC1 HTTP1 HUGO1 HYPER-V1 INDEX1 IP2 IPTABLES1 IPV61 KEYCLOAK1 KEYGEN3 KEYSTONE1 KOLLA1 KVM2 LE1 LIBRENMS1 LINUX32 LOGO1 MAAS1 MATTERMOST1 MEGACLI1 MELLANOX1 MELTDOWN1 MEMCACHED1 MIKROTIK2 MOUSE1 MTP1 MYSQL4 NAMED1 NAT1 NETBOX1 NETBOX-IPAM1 NETWORK-MANAGER1 NETWORKING10 NEUTRON1 NOVA1 NOVNC1 NPS1 NVIDIA2 OPENNEBULA1 OPENSTACK13 OPENSTACK-QUEENS5 OPENSWITCH1 OPENVSWITCH1 OVN1 PAM1 PCI1 PKI1 PORT1 PRINTER1 PROXMOX1 PUTTY1 PYTHON1 QEMU5 RABBITMQ1 RADIUS1 RADOSGW2 RAID3 RBD3 ROCKY-GLANCE1 ROUTING1 SCRIPT1 SECURITY1 SERVER1 SERVER-20121 SMTP1 SNMP1 SPECTRE1 SPEEDTEST1 SSH5 SSL1 SVG1 SWAP1 SYSCOMMANDS1 TCP1 TCP-DUMP1 TCPDUMP1 TROUBLESHOOTING5 UBUNTU4 UBUNTU-182 UBUNTU-201 UBUNTU-GNOME1 UBUNTU171 UEFI1 VAGRANT2 VIRTUAL-NETWORK1 VIRTUALISATION1 VLAN1 VM2 VPN1 VXLAN2 WINDOWS2 WINDOWS-AD1 WIRESHARK1 YOUTUBE-DL2
[A~Z][0~9]

Copyright 2022-  . All Rights Reserved

to-top