GNS3. Basic Installation.

Introduction This post gives an overview of GNS3 software and shows how to install it. It is a part of GNS3 Tutorial series. What is GNS3? GNS3 is a free network emulation software with GUI that can be used to run real network OS (for example, Cisco IOS) images, and build various network topologies in

Cisco CME and “SIP/2.0 488 Not Acceptable Here”

Introduction I have recently had a strange issue with call transfers on CME 12.0. I was getting “SIP/2.0 488 Not Acceptable Here” from ISP while trying to transfer a call from PSTN to another extension. Let’s see how we can solve this problem and make the transfer work. Equipment Used The phone I used was

How to capture traffic on Cisco ISR 4000 ?

Introduction In this article we will see how we can capture and export network traffic on a Cisco ISR 4331. The provided instructions are applicable to any Cisco ISR 4000 series router. The exported traffic has a pcap file format and therefore can be easily opened and analyzed in Wireshark. The ISR 4331 used in

Load SIP Firmware to Cisco 7900 IP Phones.

Introduction In this post we will learn how to upload SIP firmware to Cisco 7911 IP Phone. This will make possible using the phone with third party SIP servers. The instruction below applies to all Cisco 7900 series IP phones. Step 1. Download the SIP firmware. Before we start, let’s download the required SIP firmware

Cisco IP Phone Firmware Upgrade on CME.

Introduction This article show step by step how to upgrade the firmware of a Cisco IP phone managed by CME(Call Manager Express). I will be upgrading Cisco 8851 IP phone(from version 12-0-1-11 to 12-5-1SR3-74) using Cisco ISR4331/K9 router as a CME. Step 1. Download the firmware files The first thing we need to do is

Voice VLAN on HPE OfficeConnect 1920S.

Introduction In this post we will configure voice vlan on HPE OfficeConnect 1920S switch. The switch will be used for connecting Cisco 8851 IP phone, which will detect the Voice VLAN and get an IP address from the correct VLAN. The PC connected through the IP phone will remain in a Data VLAN. The exact

IRF stack configuration (2 x HPE 5130 switches).

Introduction In this article we will setup an IRF stack with two HP 5130 switches that run Comware OS. What is IRF? IRF (Intelligent Resilient Framework) is a proprietary virtualization/stacking technology used in some HPE switches. It has been developed originally by H3C, but later HPE acquired H3C. IRF allows us to interconnect several switches