Ubuntu 18.04 Crashing on vmWare ESXi Server and Carrots

Internal scenario recently. Some Ubuntu Server guest VMs running on top of vmWare ESXi server. Everything running fine, no issues, then the Ubuntu guest VMs will just randomly become utterly unresponsive. Nothing happening before, the only thing on the Ubuntu guest logs are just a crap ton of carrot jibberish: “^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@” Luckily I came across this post related to Mastodon

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SSH and FTP Slow Authentication, DBUS and Logind Restart

Fairly interesting Plesk Onyx, ProFTPD, DBUS and Logind scenario recently. Had a server sporadically terminating FTP sessions that were working fine previously. After verifying overall connectivity and firewalling were not the issue time to start diging through logs. While I could see the incomplete and terminated FTP sessions, there was nothing incredibly insightful as to why. Seeing the FTP daemon

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Stop WordPress Login Brute Force Attacks

WordPress Brute Force Attacks WordPress’ popularity not only attracts bloggers but also hackers. Hackers try to compromise WordPress installations to send spam, setup phishing exploits or launch other attacks. While there are many sophisticated attacks against WordPress, hackers often use a simple brute force password attack. In these attacks, botnets try to guess your admin password. You may think that

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Change Linux Primary IP Address Without Losing Connectivity

You need to change an IP address of an interface on a Linux server without loosing connectivity, so here’s one way: First add a secondary IP address to the interface: ip addr add 192.168.1.10/24 dev eth0 ip addr show eth0 And confirm: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP link/ether 44:38:39:00:11:aa brd ff:ff:ff:ff:ff:ff inet 192.168.1.5/24 scope global eth0 inet 192.168.1.10/24

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MySQL Buffered warning: Changed limits: max_connections: 214 (requested 800)

This is always an interesting one, comes up from time to time especially if you run a server with heavy database traffic. Possibly you’ve modified you my.cnf with various tweaked settings for ‘max_connections’ or ‘open_files_limit’ but your your ‘mysqld.log’ you start getting: [Warning] Buffered warning: Changed limits: max_open_files: 1024 (requested 5000) [Warning] Buffered warning: Changed limits: max_connections: 214 (requested 800)

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Ubiquiti ER-X EdgeRouter Increase Performance Tweak

If your like most home/office network tweakers looking for every bit of performance you can squeeze out of your home network. For $49 the small, yet powerful Ubiquiti ER-X is a great value offering gigabit ports, PoE, small form factor and VPN functionality. As with any router the manufacturers release software updates periodically that offer fixes, security patches and added

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Cisco ASA 5508-X FirePower Threat Defense Appliance Reimage

Recently I was given a Cisco ASA 5508-X Firepower Threat Defense appliance to deploy. While these are the same hardware platform as the tried-true Cisco ASA 5508 firewalls, these run Cisco’s new ‘unified’ SourceFire linux based operating system (asa-ftd), which is essentially an operating system combining the SourceFire FirePower functionality with Cisco’s conventional firewalling capabilities. It’s Cisco’s new direction for

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