1 - Set ulimit flag when running docker container docker run -it --ulimit nofile=4096 memcached 2 - Start memcached with the conn-limit flag which ideally is inherited from 'ulimit -n' 3 - Check your config per screnshot Example memcahed start script 1#!/bin/sh 2# Memcached will run as a process under the memcache …

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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 …

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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!

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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 …

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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 …

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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 …

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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)) - …

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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 …

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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 …

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Sometimes it's a necessary evil to make a bootable windows USB using your Ubuntu\Linux machine. If that terrible day ever arrives, you now have the tools to help. sudo bash woeusb-5.2.4.bash --device Win10_21H2_English_x64.iso /dev/sdb --target-filesystem NTFS For eveyrthing other than a Windows USB I normally use …

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