RSTP Alternative Port vs Backup Port

Posted on December 13, 2022 by admin

The following is some basic info on STP and RSTP. This list is not comprehensive. Refer to the link at the bottom of the page for more in depth details.

RSTP Priority

Default Priority is 32768 + VLAN ID

For example, if we are using vlan 10, then our default priority is 32768 + 10 = 32778

RSTP Priority can be set from 0 – 61440 in increments of 4096.

RSTP Port Roles

Ports can fill 1 of 4 roles.

Port Role	Description
Root Port	Port closest to the Root Bridge (Switches going to the Root switch)
Designated Port	Ports going away from the Root Bridge (To clients)
Alternate Port	A “backup” port for the Root port. If the Root Port fails, this port takes over
Backup Port	Essentially a backup port for the designated port

RSTP Port Roles

RSTP Port States

A port can be in one of 3 states. Well technically 4 states if you include down/unplugged.

Port State	Description
Discarding	Port discards packets (Alternate and Backup Ports)
Learning	Port learns MACs and doesn’t forward data
Forwarding	Port forwards data and learns MACs

RSTP Port States

RSTP Port Types

There are 3 port Types. Not to be confused with port States or Roles.

Port Type	Description
Point to Point	Switch to Switch
Point to Point Edge	Edge of Network. Connected to a PC, Printer etc.
Shared	Half Duplex, Port connected to a Hub

STP/RSTP Port Types

RSTP Timers

There are three RSTP timers. STP has the same timers, but the MaxAge is 10 seconds, and the Forward Delay is used for both Learning and Listening states which takes a total of 30 seconds to complete.

Timer Name	Default Value	Description
Hello Timer	2 Seconds	Time between Hellos created by Root
MaxAge	6 Seconds (Hello Timer * 3)	How long a Switch should wait before trying to readjust the network
Forward Delay	15 Seconds	Delay used for Learning/Listening in STP. Shouldn’t be necessary if legacy bridges are not used.

RSTP/STP Timers

Port Cost

There are technically two types of cost. The newer cost values were introduced so we could use faster ethernet speeds.

By default Cisco switches use the old cost values, but they can be changed to use the new ones.

spanning-tree pathcost method long

Ethernet Speed	Old Cost	New Cost
10 Mbps	100	2,000,000
100 Mbps	19	200,000
1 Gbps	4	20,000
10 Gbps	2	2000
100 Gbps	N/A	200
1 Tbps	N/A	20

STP/RSTP Path Cost

More information can be found at the following link.

https://www.cisco.com/c/en/us/support/docs/lan-switching/spanning-tree-protocol/24062-146.html

How to Stop a Continuous Ping on Cambium Radio

Posted on December 1, 2021 by admin

The Cambium equipment comes with a nice little ping utility when you SSH to it. Very simple to use. Maybe we should say too simple.

usage: ping <host>
       ping -n <count> <host>
                count = 0 for continuous ping

So if I want to continuously ping a website, say incredigeek.com, I can put in the following

ping -n 0 incredigeek.com

Hit return and we are off to the races. But wait. I can’t get it to stop. Ctrl + C, doesn’t do anything, Ctrl + D or Ctrl +Z don’t help either.

Okay well fine. We’ll launch another terminal and ssh into it again and see what we can do. Excellent, now we are in aaand… wait… why are the ping results showing up here too? Help!!!

Buried in the heart of the helpful help command are these lines.

       ping -- Send ICMP ECHO_REQUEST packets to network hosts
    pingend -- End ICMP ECHO_REQUEST packets to network hosts

You don’t say. Well lets try typing in pingend with all the commotion going on in the terminal.

SSH+> pingend
Ping statistics for 142.250.191.206:
        Packets: Sent = 3, Received = 3, Lost = 0 (0% loss)

Well good to know. Saves having to reboot the device.

Show uptime on Cisco

Posted on December 10, 2020 by admin

You can show the uptime on a Cisco router by running the following command.

show version

It will report a bunch of information about the router. look for the line that shows the uptime.

Ubuntu 16.04 Set Static IP address using Network Manager

Posted on October 12, 2020 by admin

Replace ens160 with the connection name. “vmcli con show”

sudo nmcli connection mod ens160 ipv4.method auto

Should be able to restart the networking service or reboot the server

Baicells eNodeB – Random Stuff

Posted on August 14, 2020 by admin

SSH
Looks like Default SSH port is 27149

Software
Runs Quagga

CELL> show version
Quagga 0.99.21 ().
Copyright 1996-2005 Kunihiro Ishiguro, et al.

https://www.quagga.net/

Settings
show network config

CELL> enable
CELL# show network
% Command incomplete.
CELL# show network config
network.loopback=interface
network.loopback.ifname='lo'
network.loopback.proto='static'
network.loopback.ipaddr='127.0.0.1'
network.loopback.netmask='255.0.0.0'
network.lan=interface
network.lan.proto='static'
network.lan.ipaddr='192.168.150.1'
network.lan.netmask='255.255.255.0'
network.lan.mtu='1496'
network.lan.ifname='eth2.3'
network.wan=interface
network.wan.ifname='eth2'
network.wan.media='copper'
network.wan.proto='dhcp'
network.defRouteIf=defRouteIf
network.defRouteIf.defRouteIf='wan'
CELL#

Users

CELL# show user
User      Permission    State
---------------------------------
admin     admin         unlocked
anonymous admin         unlocked
---------------------------------
CELL#

User commands

CELL# user
 USERNAME User name
 add Add user
 delete Delete user
 lock User lock
 role User role
 unlock User unlock
CELL# user

Mikrotik – bridge port received packet with own address as source address (), probably loop

Posted on February 5, 2020 by admin

Sometime the following warning can show up in the log.

10:48:45 interface,warning ether2: bridge port received packet with own address as source address (74:4d:28:69:89:9d), probably loop

Check and verify that your interface MAC addresses are unique. VLANs look to be the exception as they should share the MAC address of the interface the VLAN is on.

More information in this thread.
https://forum.mikrotik.com/viewtopic.php?p=583064#p703228

Disable Network Manager in CentOS

Posted on September 20, 2019 by admin

Disable the service from starting on system boot

systemctl disable NetworkManager

Stop the service from running

systemctl stop NetworkManager

And if you want to remove it from the system.

yum remove NetworkManager

Refer to this post if you need to set a static IP Address

Set static ip address in Ubuntu 19.04

Posted on August 30, 2019 by admin

The network configuration settings for the server edition of Ubuntu are now stored in the following location. Create the file if it does not exist.

sudo vi /etc/netplan/01-network-manager-all.yaml

Add or edit the config file to the following. Change eno1 to your interface name and the address and gateway to the appropriate IP’s

For more information, see netplan(5).
 network:
   version: 2
   renderer: networkd
   ethernets:
     eno1:
      dhcp4: no
      addresses: [192.168.200.24/24]
      gateway: 192.168.200.1
      nameservers:
        addresses: [8.8.8.8,8.8.4.4]

Now apply the changes with the following command.

sudo netplan apply

Cisco turn on remote log

Posted on July 12, 2019 by admin

Swap out logserveraddress with the ip or hostname of your remote log server

terminal config
logging on
logging logserveraddress
quit
wr

Find IP address from command line on Linux

Posted on May 3, 2019 by admin

Using ip command

ip add

example output

bob@localhost:~$ ip add
 1: lo:  mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
     link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
     inet 127.0.0.1/8 scope host lo
        valid_lft forever preferred_lft forever
     inet6 ::1/128 scope host
        valid_lft forever preferred_lft forever
 2: eno1:  mtu 1500 qdisc mq state UP group default qlen 1000
     link/ether 38:ea:a7:13:a4:fe brd ff:ff:ff:ff:ff:ff
     inet 192.168.1.21/24 brd 192.168.1.1 scope global dynamic noprefixroute eno1
        valid_lft 513sec preferred_lft 513sec
     inet6 13ac::98fe::ae78:d1ff/64 scope link noprefixroute
        valid_lft forever preferred_lft forever
 bob@localhost:~$

ifconfig

You may need to install net-tools to use

ifconfig

example output

bob@localhost:~$ ifconfig 
eno1: flags=4163  mtu 1500
         inet 192.168.200.58  netmask 255.255.255.0  broadcast 192.168.1.21
         inet6  13ac::98fe::ae78:d1ff  prefixlen 64  scopeid 0x20
         ether b8:ac:6f:91:01:e8  txqueuelen 1000  (Ethernet)
         RX packets 184950632  bytes 9487577263452
         RX errors 0  dropped 0  overruns 0  frame 0
         TX packets 128473456  bytes 234612443785 
         TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

Using the hostname command

hostname -I

Output is just the IP address. Example below

192.168.1.21

Incredigeek

Tag Archives: networking

RSTP Alternative Port vs Backup Port

RSTP Priority

RSTP Port Roles

RSTP Port States

RSTP Port Types

RSTP Timers

Port Cost

How to Stop a Continuous Ping on Cambium Radio

Show uptime on Cisco

Ubuntu 16.04 Set Static IP address using Network Manager

Baicells eNodeB – Random Stuff

Mikrotik – bridge port received packet with own address as source address (), probably loop

Disable Network Manager in CentOS

Set static ip address in Ubuntu 19.04

Cisco turn on remote log

Find IP address from command line on Linux