US Region

Grandmetric LLC
Lewes DE 19958
16192 Coastal Hwy USA
EIN: 98-1615498
+1 302 691 94 10

EMEA Region

ul. Metalowa 5, 60-118 Poznań, Poland
NIP 7792433527
+48 61 271 04 43


Grandmetric LTD
Office 584b
182-184 High Street North
E6 2JA
+44 20 3321 5276

  • en
  • pl
  • Spanning Tree Protocol (STP) Configuration

    Spanning Tree Protocol (STP) Configuration

    The Spanning Tree Protocol (STP) is defined by IEEE standard 802.1D-1988. The STP generates a single spanning tree inside a network. Such mode proved to be useful for supporting applications and protocols in which frames are delivered out of sequence or as duplicates. The topology is named Spanning Tree, because it is constructed as a […]

    Date: 21.09.2020

    Router on a stick approach – Cisco configuration

    A router on a stick is one of the ways to allow routing between VLANs. That kind of a setup consists of a router and a switch connected through one Ethernet link configured as an 802.1q trunk link. Such a configuration is typical in networks where no layer-3 switch exists. But first, let’s find out […]

    Date: 16.07.2020

    Author: Karol Piatek

    Span port configuration

    We’re going to use a simplified network type in this configuration manual. I’ll show you how to set up a span port. Access the switch via Telnet. Though for security reasons it is recommended to use SSH connection. Log in to the switch enter enable mode, and then configure terminal. You’ll only need two commands […]

    Date: 14.07.2020

    Rapid Spanning Tree Protocol (Cisco)

    Technology: Switching Area: RSTP Vendor: Cisco Software: 12.X , 15.X Platform: Catalyst platforms Rapid Spanning Tree Protocol also known as IEEE 802.1w is a newer version of STP that provides faster convergence than its predecessor. RSTP retain backward compatibility. Moreover, the terminology remains the same as the original 802.1D terminology, as well as most parameters, […]

    Date: 03.06.2020

    Author: Karol Piatek

    Rommon upgrade via FTP (Cisco)

    Start from verifying the current version of ROMMON. It is done with the show module command, and is listed under “Fw Version” Download the desired ROMMON image from official Cisco website and put it on a device which will act as a server for the FTP transfer. Upload the ROMMON image to the ASA flash […]

    Date: 01.06.2020

    IOS upgrade via FTP (Cisco)

    Technology: Setup Area: Setup Vendor: Cisco Software: 12.X , 15.X, IP Base, IP Services, LAN Base, LAN Light Platform: Catalyst 2960-X, Catalyst 3560 The firmware is a program which controls the operation and functionality of the switch. This is a mixture of software and hardware that has program code and data stored in it for […]

    Date: 30.04.2020

    Author: Karol Piatek

    EtherChannel Configuration

    EtherChannel Configuration An EtherChannel consists of individual Gigabit Ethernet or 10-Gigabit Ethernet links bundled into a single logical link as shown in Figure 1. Figure 1: Typical EtherChannel Configuration The EtherChannel provides full-duplex bandwidth up to 8 Gb/s (Gigabit EtherChannel) or 80 Gb/s (10-Gigabit EtherChannel) between one switch and another switch or host. When setting […]

    Date: 07.04.2020

    Allow only telnet to device (Cisco)

    Technology: Security Area: Device Hardening Vendor: Cisco Title: How to allow SSH only to Cisco device Software: 12.X , 15.X Platform: Catalyst switches, Routers Telnet protocol enables TCP/IP connections to a host fro management purposes. To allow only telnet sessions to device use configuration under line vty as below. To restrict Telnet Session one has […]

    Date: 02.11.2017

    Author: Marcin Bialy

    Allow only SSH to device (Cisco)

    Technology: Security Area: Device Hardening Vendor: Cisco Title: How to allow SSH only to Cisco device Software: 12.X , 15.X Platform: Catalyst switches, Routers Secure Shell (SSH) is a protocol used when one wants to have vides a secure remote access connection to network devices. Communication between the client and server is encrypted in both SSH version 1 […]

    Date: 02.11.2017

    Author: Marcin Bialy

    Access List example (Cisco)

    Technology: Network Security Area: ACL Vendor: Cisco Software: IOS 12.X , 15.X Platform: ISR, ASR, Catalyst Switches Access lists provides basic traffic filtering capabilities. Access lists can be configured for all routed network protocols to filter the packets of those protocols as the packets pass through a router or switch. The main rule is that […]

    Date: 12.10.2017

    Author: Marcin Bialy
    Load more
    Show all