Networking

  • Comments About Networking Technology


    We've noticed in many ways that traditional networking even in WANs and LANs has changed very little. Years ago most networks were running on 100mbit and today most still are. Even the average internet connection is largely unchanged from several years ago with some minor exceptions from Europe and Asia.
  • HP Procurve Switch 2824 CLI Telnet Experience , Guide and Tutorial


    telnet 192.168.1.54 ------------------------------------- ProCurve J4903A Switch 2824 Software revision I.10.77 Copyright (C) 1991-2009 Hewlett-Packard Co. All Rights Reserved. RESTRICTED RIGHTS LEGEND Use, duplication, or disclosure by the Government is subject to restrictions as set forth in subdivision (b) (3) (ii) of the Rights in Technical Data and Computer Software clause at 52.227-7013. HEWLETT-PACKARD COMPANY, 3000 Hanover St., Palo Alto, CA 94303 We'd like to keep you up to date about: * Software feature updates * New product announcements * Special events Please register your products now at: www.ProCurve.com Press any key to continue ------------------------------------------- LACP Problems - Be Warned - Disable LACP Unless You Need It! Disable LACP, this is the link aggregation protocol where you can combine 4 ports to increase the overall bandwidth. This sure sounds great but all LACP ports should be disabled unless you are using it. The reason is because it often takes down ports of computers/servers for no apparent or justified reason and it is a pain to troubleshoot. LACP should only be enabled on ports that are actually going to use LACP. Symptoms in the log are as follows: I 01/02/90 01:41:36 ports: port 7 is Blocked by LACP I 01/02/90 01:41:39 ports: port 7 is now on-line I 01/02/90 01:45:23 ports: port 7 is now off-line I 01/02/90 01:45:48 ports: port 7 is Blocked by LACP I 01/02/90 01:45:51 ports: port 7 is now on-line I 01/02/90 01:56:47 ports: port 7 is now off-line I 01/02/90 02:22:42 ports: port 7 is Blocked by LACP I 01/02/90 02:22:42 ports: port 7 is now off-line I 01/02/90 02:39:44 ports: port 7 is Blocked by LACP I 01/02/90 02:39:47 ports: port 7 is now on-line I 01/02/90 02:45:15 ports: port 7 is now off-line I 01/02/90 02:56:42 ports: port 7 is Blocked by LACP I 01/02/90 02:56:45 ports: port 7 is now on-line I 01/02/90 02:57:44 ports: port 7 is now off-line #check if you have lacp enabled on any ports show lacp no LACP ports found. How to disable LACP: *Warning if you have machines that do not come back automatically if the link goes up and down be warned that this could take some or all machines offline and needs physical intervention. When I typed the "no interface all lacp" this took down most computers on the switch and they did not come back on their own except a few. ProCurve Switch 2824# config ProCurve Switch 2824(config)# ProCurve Switch 2824(config)# no interface all lacp wr mem Disable port *Warning about port disable/enable is that I find some servers detect the uplink but will not work after being re-enabled without a network restart (eg. service network restart The "8" represents port numbers. You can also do a range such as "8-15" config int ethernet 8 disable --------------------------- Enable Port *Warning about port disable/enable is that I find some servers detect the uplink but will not work after being re-enabled without a network restart (eg. service network restart config int ethernet 8 enable ------------------------------------ Check each port's bandwidth usage in mbit The "Util" field is how many mbit per second the port is doing. You need to base the % percentage off the port speed eg. 10,100 or 1000 mbit. Port Mode | --------------------------- | --------------------------- | Kbits/sec Pkts/sec Util | Kbits/sec Pkts/sec Util --------- -------- + ---------- ---------- ----- + ---------- ---------- ----- 1 1000FDx | 5016 15 00.50 | 5040 47 00.50 2 1000FDx | 0 0 0 | 0 0 0 3 1000FDx | 2536 0 00.25 | 5024 32 00.50 4 1000FDx | 12376 691 01.23 | 5352 448 00.53 5 1000FDx | 600 0 00.06 | 5024 32 00.50 6 1000FDx | 3960 0 00.39 | 5024 32 00.50 7 1000FDx | 5360 77 00.53 | 5344 112 00.53 8 1000FDx | 0 0 0 | 0 0 0 9 1000FDx | 2488 0 00.24 | 5024 32 00.50 10 1000FDx | 2536 0 00.25 | 5024 32 00.50 11 1000FDx | 2488 0 00.24 | 5024 32 00.50 12 1000FDx | 2472 0 00.24 | 5024 32 00.50 13 1000FDx | 0 0 0 | 0 0 0 14 1000FDx | 0 0 0 | 0 0 0 15 1000FDx | 0 0 0 | 0 0 0 16 1000FDx | 0 0 0 | 0 0 0 17 1000FDx | 0 0 0 | 0 0 0 18 1000FDx | 0 0 0 | 0 0 0 19 1000FDx | 5680 538 00.56 | 12760 784 01.27 20 100HDx | 0 0 0 | 520 32 00.52 21 1000FDx | 0 0 0 | 0 0 0 22 1000FDx | 0 0 0 | 0 0 0 23 1000FDx | 0 0 0 | 0 0 0 24 1000FDx | 0 0 0 | 0 0 0 ------------------------------------------------------------- Show What Port MAC Address Belongs To show mac 00:1F:D0:00:13:CC Status and Counters - Address Table - 001fd0-0013cc MAC Address : 001fd0-0013cc Located on Port : 8 Show All MAC Addresses By Port show mac all If no MAC is displayed it means no device is connected or the device is not active or the port on the switch may be bad or disabled. Status and Counters - Port Address Table - 17 MAC Address ------------- show specific port mac show mac 10 Check overall port status show interfaces is very useful for counting traffic and also identifying network issues Status and Counters - Port Status | Intrusion MDI Flow Bcast Port Type | Alert Enabled Status Mode Mode Ctrl Limit ----- --------- + --------- ------- ------ ---------- ----- ----- ------ 1 100/1000T | No Yes Up 1000FDx MDIX off 0 2 100/1000T | No Yes Down 1000FDx MDIX off 0 3 100/1000T | No Yes Up 1000FDx MDI off 0 4 100/1000T | No Yes Up 1000FDx MDIX off 0 5 100/1000T | No Yes Up 1000FDx MDIX off 0 6 100/1000T | No Yes Up 1000FDx MDI off 0 7 100/1000T | No Yes Up 1000FDx MDI off 0 8 100/1000T | No No Down 1000FDx MDI off 0 9 100/1000T | No Yes Up 1000FDx MDI off 0 10 100/1000T | No Yes Up 1000FDx MDI off 0 11 100/1000T | No Yes Up 1000FDx MDI off 0 12 100/1000T | No Yes Up 1000FDx MDI off 0 13 100/1000T | No Yes Down 1000FDx MDI off 0 14 100/1000T | No Yes Down 1000FDx MDI off 0 15 100/1000T | No Yes Down 1000FDx MDIX off 0 16 100/1000T | No Yes Down 1000FDx MDIX off 0 17 100/1000T | No Yes Down 1000FDx MDIX off 0 18 100/1000T | No Yes Down 1000FDx MDIX off 0 19 100/1000T | No Yes Up 1000FDx MDIX off 0 20 100/1000T | No Yes Up 100HDx MDIX off 0 21 100/1000T | No Yes Down 1000FDx MDIX off 0 22 100/1000T | No Yes Down 1000FDx MDI off 0 23 100/1000T | No Yes Down 1000FDx MDI off 0 24 100/1000T | No Yes Down 1000FDx MDIX off 0 show interfaces gives you more detail Notice Port 7 showing 203 "Errors Rx". It was because of a bad cable and we wondered why that server had spotty connectivity. Status and Counters - Port Counters Flow Bcast Port Total Bytes Total Frames Errors Rx Drops Rx Ctrl Limit ----- ------------ ------------ ------------ ------------ ----- ------ 1 3,164,403... 2,285,255... 0 0 off 0 2 457,687,164 2,150,118... 0 0 off 0 3 3,716,409... 2,795,214... 14 0 off 0 4 1,897,977... 2,207,705... 0 0 off 0 5 626,012,466 3,843,597... 0 0 off 0 6 2,628,057... 2,138,559... 0 0 off 0 7 1,498,582... 476,790,025 0 0 off 0 8 2,830,274... 1,696,622... 589 0 off 0 9 1,573,201... 3,990,337... 0 0 off 0 10 1,930,438... 2,808,292... 238 0 off 0 11 3,137,823... 3,577,438... 1476 0 off 0 12 2,363,525... 99,291,760 1102 0 off 0 13 0 0 0 0 off 0 14 0 0 0 0 off 0 15 0 0 0 0 off 0 16 0 0 0 0 off 0 17 0 0 0 0 off 0 18 0 0 0 0 off 0 19 2,186,889... 2,963,434... 1 0 off 0 20 530,240,341 746,865,357 581 0 off 0 21 1866 7 2 0 off 0 22 2288 7 2 0 off 0 23 2246 7 2 0 off 0 24 190,610 1821 2 0 off 0 Password Issues/Requirements Note that these switches support a maximum of 16 characters. Spaces cannot be used and it is not obvious if you have gone over the limit so if you cannot login after setting a password type it out and count 16 characters and use only those and you should be able to login. If your password is lost/unknown you can reset just the password (not the switch settings) by holding the "Clear" button on the front of the switch for at least 1 second. Note again this does not reset the switch config but only the password when done this way.
  • Windows Server 2012, 2016, 2019 How To Install and Missing Disabled Telnet Client


    By default telnet is not enabled or installed on the latest Windows servers so you'll get an error saying: telnet is not recognized as an internal or external command dism /online /Enable-Feature /FeatureName:TelnetClient
  • Cisco Switch Setup Guide Command List


    Enter configuration console: enable configure terminal This is important because if your console doesn't look like below none of the commands will work! Switch(config)# Show Switch Configuration: show run Show Port List/Status: Switch#show interface status Port Name Status Vlan Duplex Speed Type Fa0/1 connected 1 a-full a-100 10/100BaseTX Fa0/2 notconnect 1 auto auto 10/100BaseTX Fa0/3 notconnect 1 auto auto 10/100BaseTX Fa0/4 notconnect 1 auto auto 10/100BaseTX Fa0/5 notconnect 1 auto auto 10/100BaseTX Fa0/6 notconnect 1 auto auto 10/100BaseTX Fa0/7 notconnect 1 auto auto 10/100BaseTX Fa0/8 notconnect 1 auto auto 10/100BaseTX Fa0/9 notconnect 1 auto auto 10/100BaseTX Fa0/10 notconnect 1 auto auto 10/100BaseTX Fa0/11 notconnect 1 auto auto 10/100BaseTX Fa0/12 notconnect 1 auto auto 10/100BaseTX Fa0/13 notconnect 1 auto auto 10/100BaseTX Fa0/14 notconnect 1 auto auto 10/100BaseTX Fa0/15 notconnect 1 auto auto 10/100BaseTX Fa0/16 notconnect 1 auto auto 10/100BaseTX Fa0/17 notconnect 1 auto auto 10/100BaseTX Fa0/18 notconnect 1 auto auto 10/100BaseTX Fa0/19 notconnect 1 auto auto 10/100BaseTX Fa0/20 notconnect 1 auto auto 10/100BaseTX Fa0/21 notconnect 1 auto auto 10/100BaseTX Fa0/22 notconnect 1 auto auto 10/100BaseTX Fa0/23 notconnect 1 auto auto 10/100BaseTX Fa0/24 notconnect 1 auto auto 10/100BaseTX Gi0/1 connected 1 a-full a-1000 10/100/1000BaseTX Gi0/2 notconnect 1 auto auto Not Present Show config of individual port or vlan You could also have used "interface vlan 1" and you would get the config of the vlan. Switch#show running-config interface gi0/1 Building configuration... Current configuration : 36 bytes ! interface GigabitEthernet0/1 end Show all VLANs: show vlan VLAN Name Status Ports ---- -------------------------------- --------- ------------------------------- 1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/4 Fa0/5, Fa0/6, Fa0/7, Fa0/8 Fa0/9, Fa0/10, Fa0/11, Fa0/12 Fa0/13, Fa0/14, Fa0/15, Fa0/16 Fa0/17, Fa0/18, Fa0/19, Fa0/20 Fa0/21, Fa0/22, Fa0/23, Fa0/24 Gi0/1, Gi0/2 1002 fddi-default act/unsup 1003 token-ring-default act/unsup 1004 fddinet-default act/unsup 1005 trnet-default act/unsup VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2 ---- ----- ---------- ----- ------ ------ -------- ---- -------- ------ ------ 1 enet 100001 1500 - - - - - 0 0 1002 fddi 101002 1500 - - - - - 0 0 1003 tr 101003 1500 - - - - - 0 0 1004 fdnet 101004 1500 - - - ieee - 0 0 1005 trnet 101005 1500 - - - ibm - 0 0 Show Specific VLAN show vlan id 1 Configure interfaces 100M Ethernet is normally known as fa0 So for port 1 you would use fa0/1 int fa0/1 or int fastethernet0/1 1Gig Ethernet known as gigabitethernet or gi0 int gigabitethernet0/1 or int gi0/1 You can configure vlans in the same way: int vlan 1 Working with a range of ports (example of ports 1-12) int range fa0/1-12 Enable Port(s) int fa0/1 no shutdown The no in front of shutdown means turn on the port (the opposite or !) How to Assign ports to vlan #how to assign ports to vlan in this case it is ports 1-24 and they are being assigned to vlan 1 Switch(config)#int range fa0/1-24 Switch(config-if-range)#switchport mode access Switch(config-if-range)#switchport access vlan 1
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