SSHD mm_request_send: write: Broken pipe

You are attempting to login to a Linux machine (probably CentOS) and your SSH sessions are instantly disconnected. /var/log/secure shows various Signal 15 crashes and this error: mm_request_send:  write:  Broken pipe Your box has been hacked.    Format and Reinstall. Be sure to run “yum update” at frequent intervals to keep your servers/VMs up-to-date!!     ...

Connect Error (2000) mysqld cannot connect to MySQL 4.1+ using old authentication ERROR 2049 (HY000): Connection using old (pre-4.1.1) authentication protocol refused

You are receiving these errors: Connect Error (2000) mysqld cannot connect to MySQL 4.1+ using old authentication ERROR 1275 (HY000): Server is running in –secure-auth mode, but ‘dbname’@’localhost’ has a password in the old format; please change the password to the new format ERROR 2049 (HY000): Connection using old (pre-4.1.1) authentication protocol refused (client option ...

Convert squid log timestamps to human readable

Convert squid log timestamps to a human readable format: cat access.log | perl -p -e 's/^([0-9]*)/"[".localtime($1)."]"/e'

Shell Script Remove All Blank Links

Use the following ‘awk’ command to remove all blank lines from a file: awk ‘NF > 0’ filename

pfSense Transparent Bridge Firewall + VMware ESXi

You have setup pfSense as a VM via the OVA. Your VM that you want to filter its traffic is on a portgroup on a vSwitch with no uplink. pfSense has 2 NICs – 1. WAN – Using a portgroup that has internet access 2. LAN – Using the same portgroup/vswitch as your VM that ...

Disable VR (vSphere Replication) on VM

You have long removed SRM/vSphere replication. You discovered a VM still had vSphere Replication enabled. system has paused replication disk added to vm Manually remove vSphere replication from vCenter 1. In a webbrowser go to: http://YOUR-vCenter Server/mob 2. Remove this extensions: “com.vmware.vcHms” More information about MOB, and removing plugins from vCenter, here: Remove vSphere ...

VMware Tools For FreeBSD

cd /usr/ports/emulators/open-vm-tools-nox11/ make all install vi /etc/rc.conf vmware_guest_vmblock_enable=”YES” vmware_guest_vmhgfs_enable=”YES” vmware_guest_vmmemctl_enable=”YES” vmware_guest_vmxnet_enable=”YES” vmware_guestd_enable=”YES” vi /etc/ntp.conf First line: tinker panic 0 vi /boot/loader.conf kern.hz=100 vi /etc/sysctl.conf vmware-toolbox-cmd timesync disable

CentOS / RHEL horrible disk performance with SSD

noop, is essentially a first-in first-out (FIFO) queue with no extra logic. Each virtual machine can stop worrying about the disk, instead passing I/O requests along to the hypervisor to make a better decision about overall performance. Add “elevator=noop” to the kernel parameters in your boot loader’s configuration in /etc/grub.conf `echo noop > /sys/block/${DEVICE}/queue/scheduler`. Set ...

Shrink Postgres Tables / Databases

psql With psql cli: vacuum full; also do: reindex ;


List off all the rules in order. This helps to see if an allow is overriding one of your denies: iptables -nvL –line-numbers Reject or Drop? Drop means to drop everything at the interface and give no response. Best for port probes and the like. Reject responds to the source. Best practices for TCP/IP