Write to a file in CSharp

Quick and dirty way to write to a file in C#.

StreamWriter log = new StreamWriter(@c:\log.txt);

log.WriteLine(ErrorMessage);

log.WriteLine();

log.Close();

Setup iptables in Linux

Ubuntu does come with iptables preset like in Fedora. Here's the base set up for iptables.

Add iptable rules.

Block Null Packets

iptables -A INPUT -p tcp --tcp-flags ALL NONE -j DROP

Reject Syn-Flood Attack

iptables -A INPUT -p tcp ! --syn -m state --state NEW -j DROP

Reject XMAS/recon packets

iptables -A INPUT -p tcp --tcp-flags ALL ALL -j DROP

Allow custom ports

<here>

Accept Established Connections

iptables -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT

iptables -A INPUT -j REJECT iptables -A FORWARD -j REJECT

iptables -A FORWARD -i eth0 -m state --state RELATED,ESTABLISHED -j ACCEPT

iptables -A FORWARD -j REJECT

iptables -A OUTPUT -m state --state NEW,RELATED,ESTABLISHED -j ACCEPT

Use iptables-save to save it to a file.

iptables-save > /etc/iptables.rules

Edit rc.local to import iptables rules during boot up.

iptables-restore < /etc/iptables.rules

Get VMX and VMWare tools version and export to CSV

To get the VMware tools versions and export it to a csv called vmtools.csv

get-vm | where {$_.powerstate -ne "PoweredOff" } | where {$_.Guest.ToolsVersionStatus -ne "guestToolsCurrent"} | % { get-view $_.id } | select Name, @{ Name="ToolsVersion"; Expression={$_.config.tools.toolsVersion}}, @{ Name="ToolStatus"; Expression={$_.Guest.ToolsVersionStatus}} | Export-Csv -NoTypeInformation -UseCulture -Path d:\vmtools.csv

Tarball an entire Linux system

#!/bin/bash

#Version: 1.0

#Description:  Checks for a destination mount directory.  Mounts it if it does not exist, the backs up the server to the mount directory.

mountdir="<mount directory>"

servername="<servername>"

exclusions="--exclude=/mnt --exclude=/proc --exclude=/lost+found --exclude=/tmp --exclude=/media --exclude=/sys --exclude=/dev --exclude=/run --exclude=/var/cache"

if [ -d $mountdir ]; then

     cd $mountdir

     tar -zcpf $servername-full-backup-`date '+%d-%B-%Y'`.tar.gz / $exclusions

else

     sudo mount -t cifs -o username=moatisuser,password=moatisuser,rw \\\\fw24\\ata_1 /mnt/fw24

     cd $mountdir

     tar -zcpf $servername-full-backup-`date '+%d-%B-%Y'`.tar.gz / $exclusions

fi

Reset a slot in Cisco UCS.

- Reset a slot (equivalent to remove power from the blade and reapplying):

     #reset slot x/y (where x = chassis and y = blade or server #)

Get all vm's with connected CD rom drives

This is a powercli command to get all the vm's with connected cdrom drive.  

get-cluster | where {$_.Name -eq "SFColo Test & Dev"} | get-vm | where { $_ | get-cddrive | where { $_.ConnectionState.Connected -eq "true" } } | select Name

Power on/off VM via command line.

Power on a VM

To power on a virtual machine from the command line:

1. List the inventory ID of the virtual machine with the command:
   
   vim-cmd vmsvc/getallvms |grep <vm name>
   
   Note: The first column of the output shows the vmid.
   
2. Check the power state of the virtual machine with the command:
   
   vim-cmd vmsvc/power.getstate <vmid>
   
3. Power-on the virtual machine with the command:
   
   vim-cmd vmsvc/power.on <vmid>

vSAN troubleshooting Commands

RVC login

localhost:~ #rvc

localhost:~ #domain\user@localhost

Disk Component Resync

Show component resync status

vsan.resync_dashboard .

Show all disk status (used/reserved, disk health, disk version)

vsan.disks_stats .

Disk Rebalance

Start Rebalance disks

vsan.proactive_rebalance --start --time-span 86400 --variance-threshold 0.30 --time-threshold 1800 --rate-threshold 100000 <cluster path>

Stop Rebalance disks

vsan.proactive_rebalance --stop <cluster path>

Check Rebalance status

vsan.proactive_rebalance_info /localhost/SouthEast/computers/Raleigh

vsan.resync_dashboard /localhost/SouthEast/computers/Raleigh

Cluster

Remove host or witness from fault domain

esxcli vsan cluster leave

Troubleshoot

esxcli vsan cluster get

vsan.check_state .

vsan.disks_info <host path>

Stress Test

/localhost/SouthCentral/computers/Houston> vsan.health.cluster_load_test_run -r houston_stress -t "Stress test" -d 28800 ./

Check vSAN upgrade status

vsan.upgrade_status -r 60 /localhost/VSAN-DC/computers/VSAN-Cluster/ 

Decrypt Files from QNAP with OpenSSL

If you have encryption enabled on your QNAP storage, to decrypt it, do the following.

Decrypt one file
     openssl enc -d -aes-256-cbc -k <decrypt password> -in filename.jpg -out filename.jpg


Decrypt multiple files in a folder.
     for f in * ; do [ -f $f ] && openssl enc -d -aes-256-cbc -k <decrypt password> -in $f -out _$f;

Change Network Failover Detection Policy on vSwitches and Portgroups

This script traverses all clusters and host and check if Beacon Probing is set the NetworkFailoverDetectionPolicy.  If Beacon Probing is set, change it to Link Status.

#import-module VMware.VimAutomation.Core

#Connect-VIServer -Server vcenter_hostname

#uncomment for testing

#$vmhosts = "hostname1","hostname2"

　

#uncomment for live run

#get the hostnames of all the hosts in every cluster

$vmhosts = get-cluster | get-vmhost | select name

foreach($vmhost in $vmhosts)

{

    #Gets all the vSwitch names that has beacon probing set on the host.

    $switch_policy = Get-VirtualSwitch -VMHost $vmhost.Name | where {$_.Name -ne "vSwitchiDRACvusb"} | Get-NicTeamingPolicy | Where-Object {$_.NetworkFailoverDetectionPolicy -eq "BeaconProbing"} | select -ExpandProperty VirtualSwitch # | select VirtualSwitch | format-wide

    if ($switch_policy)

    {

        foreach ($switch in $switch_policy)

        {

            $vs = Get-VirtualSwitch -VMHost $vmhost.Name -Name $switch

            Get-NicTeamingPolicy -VirtualSwitch $vs | Set-NicTeamingPolicy -NetworkFailoverDetectionPolicy LinkStatus

        }

    }

　

    #Gets all the port group names that has beacon probing set on the host.

    $portgroup_policy = Get-VirtualPortGroup -VMHost $vmhost | Get-NicTeamingPolicy | Where-Object {$_.NetworkFailoverDetectionPolicy -eq "BeaconProbing"} | select -ExpandProperty VirtualPortGroup

    if ($portgroup_policy)

    {

        foreach ($p in $portgroup_policy)

        {

            #Sets the nicteamingpolicy from the host and its portgroup.

            $vpg = Get-VirtualPortGroup -VMHost $vmhost.Name -Name $p

            Get-NicTeamingPolicy -VirtualPortGroup $vpg | Set-NicTeamingPolicy -NetworkFailoverDetectionPolicy LinkStatus

        }

    }

}