Here is a X-Lite free SIP phone configuration guide for Cisco CME(CUCME) 8.6.


- Cisco CME 8.6
- Cisco Router 2811 with Version 15.1(4)M8
- CME fa0/0 IP address :
- X-lite's IP address :
- Voice register global mode : CME


1. Router configuration


ip domain name wirethink.local
voice service voip
allow-connections sip to sip
redirect ip2ip
fax protocol t38 version 0 ls-redundancy 0 hs-redundancy 0 fallback none
bind control source-interface FastEthernet0/0
bind media source-interface FastEthernet0/0
registrar server
no call service stop
voice class codec 1
codec preference 1  g711ulaw
voice register global
mode cme
source-address port 5060
max-dn 10
max-pool 10
authenticate register
authenticate realm wirethink.local
timezone 12
voicemail 8005
tftp-path flash:
voice register dn  1
number 7777
allow watch
name Chris
voice register pool  1
id mac 0000.0000.0001  ;  Any MAC address for X-Lite, but CUCM
number 1 dn 1
dtmf-relay rtp-nte sip-notify
voice-class codec 1
username Chris password happy ; Authorization name "Chris", password "happy" in this case.


2. X-Lite Account Setting

- User ID : extension # "7777" in this case.
- Domain : CME IP
- Password : Password under pool 1. "happy" in this case.
- Authorization name = Username under pool 1. "Chris" in this case.





Last Updated (Tuesday, 10 November 2015 10:59)

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As a network engineer, Expect script is handy on linux environment. Since working on Windows environment with limited power to install 3rd party software. Microsoft PowerShell is one of best option for alternative. I have tried Activestate perl with Expect module and plink.exec with "-m" option to use commands. However, partially worked or constantly met limitation and comparibility issue. Ended up, decided to find something always works. Here is what I found.


PowerShell : How to use SSH.NET Library on Windows 7


1. Download

Download SSH.NET Library from below Link.


"Download Script Module and DLL file: SSH-SessionsPSv3.zip"


1-1. Unzip it

1-2. Create a folder name as "SSH-Sessions" under


* In order to create a folder under the System32 directoy, it requires admin priviliege. If you don't have admin priviliege, create a folder under user dictory. Then you need to update "PS envi path" 


1-3. Open powershell console by start > windows powersheel.

1-4. From prompt >

PS C:\WINDOWS\system32\windowspowershell\v1.0\Modules> Import-Module SSH-Sessions


1-5. Make sure "New SshSession" cmlet from list.

 * Also, make sure your power shell is version 3.



Last Updated (Wednesday, 10 February 2016 08:51)

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When cloned a CentOS 6.5 from Virtual Machine template, you might have a ethernet communication issue and getting below error messages.

"Device eth0 does not seem to be present"

The reason is that a previous/original machine already had claimed MAC address, duplicated MAC.

Here is the steps to fix it. 


1. Power on your Virtual machine (Cloned CentOS 6.5)

2. Open a file, /etc/udev/rules.d/70-persistent-net.rules.

- Edit the file and add new mac address which is not being used from previous cloning process.
* How can I get new MAC? try add new network card thru vSphere or vCenter, it will add new ethernet device on the file, 70-persistent-net.rules. See below screenshot which has few more PCI devices added.


 vmware clone VM caused eth0 issue 1


# PCI device 0x15ad:0x07b0 (vmxnet3)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", 
ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"



3. Open a file, /etc/sysconfig/network-scripts/ifcfg-eth0.





4. Verify MAC address on Virtual Machine cloned.


 vmware clone VM caused eth0 issue 2


5. Change default Gateway IP

Open a file, /etc/sysconfig/network




6. Power on the cloned Virtual Machin or or reload services .

5.1 Restart udev

# start_udev

5.2 Restart network configuration

# service network restart


7. Setup NTPD

[CentOS~]# yum install ntp ntpdate ntp-doc
[CentOS~]# chkconfig ntpd on ;Turn on service, enter
[CentOS~]# ntpdate pool.ntp.org ; Synchronize the system clock with 0.pool.ntp.org server

[CentOS~]# /etc/init.d/ntpd start ;Start the NTP server. The following will continuously adjusts system time from upstream NTP server.



I hope it is informative for you.


Last Updated (Monday, 09 March 2015 15:50)


Out of the box, Avaya ERS 55xx switch system will indicate below time clock.


ERS_5520# show clock
   System Clock time  :    THU JAN 01 00:02:01 1970
   Current SNTP time  :    Not Set
   Daylight saving recurring time is disabled
   Daylight saving time is disabled
   Time zone offset from UTC is 00:00

ERS_5520# show ntp
  NTP client enabled : false
  NTP polling interval : 15 minutes
  Last NTP update:

ERS_5520#show sntp
  SNTP Status:                    disabled
  Primary server address:
  Secondary server address:
  Sync interval:                  24 hours
  Last sync source:     
  Primary server sync failures:   1
  Secondary server sync failures: 0
  Last sync time:                 Not Set
  Next sync time:                 Not Set
  Current time:                   Not Set



Here is how to configure NTP by CLI.

Given condition

- NTP sources : &
- US Estern time zone
- Summer-time : 3/11/2013 ~ 11/4/2013.
- H/W : Avaya ERS 5500 with ver. v6.2.1.003

[Avaya ERS 5520]

ERS_5520# Conf t
ERS_5520(config)# sntp server primary address
ERS_5520(config)# sntp server secondary address
ERS_5520(config)# sntp enable
ERS_5520(config)# clock time-zone EST -5
ERS_5520(config)# clock summer-time recurring 2 sunday march 00:00 1 sunday november 00:00 60

ERS_5520(config)# clock summer-time EDT date march 11 2013 00:00 November 4 2013 00:00

* NTP summer-time recurring option is available after S/W ver.

ERS_5520# show clock




* NTP command will support by S/W ver.







Last Updated (Tuesday, 11 June 2013 14:05)


How you handle user FTP traffic? as you know there are two transfer modes, passive and active, for FTP traffic.

- Active mode : FTP Server will assign port numbers for FTP data transfer.

- Passive mode : FTP Client will fix ports numbers for FTP data transfer.
* Normally, the port number ranges are at least 10 ports.


Active FTP :
     command : client >random port ---> server 21
     data    : client >random port <- server 20

Passive FTP :
     command : client >random port -> server 21
     data    : client >random port -> server >random


You can open certain range of ports for FTP data transfer, but security point of view, it is not always the best practice. Beside, the range will be bigger than you think if you are not limiting allowed FTP servers.

If you just allow port 20-21 to outbound(destination port), you would make FTP session, but no FTP data transfer. Showing error like below.


Last Updated (Monday, 18 November 2013 06:38)

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1. Setup CSACS-1121 appliance

- Bootup system and follow the installation guide.
- Remebmer admin and pwd that you typed in during installation.
- Remember IP address of the CSACS-1121.
- Auto reboot and got prompt.

2. GUI access

- Access GUI of the CSACS-1121 from client
- Use below login credential

username : ACSAdmin
password : default

- Change default pwd to permanent



Last Updated (Friday, 10 August 2012 09:24)

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