October 29

WdsClient: An Error Occurred While Obtaining an IP Address from the DHCP server

The Problem: Trying to deploy a VM in VMWare Esxi 6.5 using a Windows 2012 R2 WDS server, the VM pops up an error, saying “WdsClient: An error occurred while obtaining an ip address from the dhcp server. Please check to ensure that there is an operational DHCP server on this network segment.”

The cause: If you setup your VM using Vmxnet3, you will see this problem as Windows 2012 R2 boot image doesn’t have the driver. If you setup your VM using E1000e nic, it will work fine.

The Solutions: Use E1000e nic if you can. If not, here are the links

VMware KB 1038585

Here is a detail instruction from Helpful IT if you choose to use VMXNET3

Category: Vmware | LEAVE A COMMENT
October 17

How to Backup and Restore Cisco Switch Config File?

Here is the original link from cisco

Use a TFTP Server to Backup and Restore a Configuration

Before you proceed with this method, make sure you have a TFTP server on the network to which you have IP connectivity.

  1. At the Router> prompt, issue the enable command, and provide the required password when prompted.

    The prompt changes to Router#, which indicates that the router is now in privileged mode.

  2. Copy the running configuration file to the TFTP server:
    CE_2#copy running-config tftp:
Address or name of remote host []? 64.104.207.171
Destination filename [ce_2-confg]? backup_cfg_for_my_router
!!
1030 bytes copied in 2.489 secs (395 bytes/sec)
CE_2#
  3. Open the configuration file with a text editor. Search for and remove any line that starts with “AAA”.

    Note: This step is to remove any security commands that can lock you out of the router.

  4. Copy the configuration file from the TFTP server to a new router in privileged (enable) mode which has a basic configuration.
    Router#copy tftp: running-config
Address or name of remote host []? 64.104.207.171
Source filename []? backup_cfg_for_my_router
Destination filename [running-config]?
Accessing tftp://10.66.64.10/backup_cfg_for_my_router...
Loading backup_cfg_for_router from 64.104.207.171 (via FastEthernet0/0): !
[OK - 1030 bytes]

1030 bytes copied in 9.612 secs (107 bytes/sec)
CE_2#
Category: Cisco | LEAVE A COMMENT
October 14

Windows 7 Windows Explorer Stopped Working When Copy File From USB Drive

Problem: 

Windows 7:  Windows Explorer has Stopped Working When Copy File From a USB Drive.

Solutions: Uninstall MyWinLocker

Or you can download ShellExView from Nirsoft and find out which extension causes the problem by disabling it.

See the picture below.

Sort the extensions by clicking “Microsoft” and right click the none Microsoft extension to disable it, until find the one that causes the problem.

Image

Category: Windows | LEAVE A COMMENT
October 6

Youtube-dl Quick Commands

Download High quality mp3 audio, and use video title as file name

youtube-dl -o '%(title)s.%(ext)s' --extract-audio --audio-format mp3 --audio-quality 0 url

 

Download High quality mp3 audios that have min view 2000, and use video title as file name, 

youtube-dl -o '%(title)s.%(ext)s' --min-view 20000 --extract-audio --audio-format mp3 --audio-quality 0 url

 

Do not download any videos with less than count views, and use video title as file name

youtube-dl  -o '%(title)s'  --min-views 1000  url

 

Download best quality video play list and use video title as file name

youtube-dl -o "%(title)s.%(ext)s" -cwi --format best --yes-playlist "url"

-cwi is a shorter alternative to –continue –no-overwrites –ignore-errors

 

Download the best video 

youtube-dl -f best url

List Available Formats

youtube-dl -F "url"

For more information:

https://github.com/rg3/youtube-dl/blob/master/README.md#readme

 

Category: Uncategorized | LEAVE A COMMENT
October 5

How to Configure Secondary IP Address on the Wan Interface for a Different Subnet Devices

A customer has two group of devices.

Subnet 192.168.1.1/24 is connected to X0.  This group devices want to use WAN IP address 24.192.156.56 as the public IP address.

Subnet 172.16.50.1/24 is connected to X4.  This group devices want to use WAN IP address 24.192.156.57 as the public IP address.

X0 LAN ZONE

X4 LAN ZONE

note: you could use different zone, dmz, wlan or lan2, etc, the following steps might need to be adjusted.

Step 1

Create a Static ARP entry for the SonicWall IP/MAC address for the secondary subnet on the Wan interface. Make sure the public entry is checked.

Step 2 (no need in my test)

Create Static ARP entry for the Gateway IP/MAC Address of the secondary subnet. ( this entry might be already created when you assign an interface x4 to a subnet)

Step 3 (no need in my test)

Add a static route for the secondary subnet to the X1 Interface without any gateway specified.( I found out that I didn’t need to do this as it was created by default.)

Step 4 

Create the Address Object for the second WAN IP Address

Step 5

Create the NAT rule for the second WAN IP and to the Second Subnet 172.16.50.1/24 devices

Please use those two links below as references.

Link1 How to configure secondary ip address on the wan interface

Link2 configuring multiple wan subnets using static ART with SonicOs enhanced

 

Category: SonicWall | LEAVE A COMMENT