Blog

• Clearing the arp table of new printers which has been replace with an Old IP address of the old printer

                  Solution: Clear IP arp (IP address of the printer)

• The device was reachable on the switch but not the command prompt

                Solution: The default gateway was wrong

• New 4400 router port was not connecting to copper cable

            Solution: Did research and realize I had to configure media-type RJ45

• Replacing a switch which has no backup

Solution: Majority of the devices connected to that switch were DHCP and few of them were printers,   So I configured port 1 to 40 to be dhcp and the rest to be printer port and at the end only three devices  were having issue and the it was trace back to assign the right Vlan

• I install a new 4400 router and after the configuration I realized telnet was not working so I had to open TAC Case with Cisco and it was resolved with below configuration

             Solution :Conf t

              nologin block-for

• Revision Number change on 3850 ( this normally happen when you don’t follow the right process during password recovery of 3850 switches)

             Solution: show version to see the correct register number

             Router (config)# no system ignore startupconfig  switch all

              Change the register back to 0x2102 or0x102:

               Router(config)#config-register 0x210

                 # reload

• Users getting wrong IP scope from the network

Got a ticket that some users are don’t have internet access and are having wrong dhcp network scope. I ask the desktop team to do nslookup and dns resolving from 192.168.x.1 which was not the company dns server. I grab the ip and logon to the core and did sh ip arp the IP address and decided to trace the port from there. Finally I found the port and it was some home router connected to port and removing it resolves the issue

• Branch office with slow performance

     Solution: Bad cable between the switch and the router

     Did a ping test on the router to 8.8.8.8 reply 100 and the was no drop but on the switch was so many drop

    So I know the issue has to be on the switch , did reboot and same issue and later check on the port to the router and had a lot CRC errors change the fiber cable it still not resolve till I changed the transceiver

• Branch office with slow performance

     Solution: Router Port set to half duplex after power outage

• Branch office with slow performance

    Solution: Upgrading the IOS which was different from   other routers performing well