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WS-C3850-24U-L does not boot

Hi, I have this switch 3850 that does not boot, I tried to boot from usb and initialize with the same error. Also the flash is not recognized. Do you have aniy idea to recover this switch form boot process? I share the logs, thanks in advance.   Init...

cipher selection in switch

Hi Switch have some week ciphers. From the below commands, we can know which cipher are available, but I am not sure which one is stronger. How can we know these ciphers? and second question is at the blow command, can we think the first one aes192-c...

zshowip by Enthusiast
  • 5 replies
  • 0 Helpful votes

input errors on Nexus 9300

I have a couple of N9K-C93108TC-EX switches seeing about half of the packets coming from a server being errors.  I can't find any detailed counters showing what the error is.  Where should I be looking? Thanks. switch# sh int e 1/8Ethernet1/8 is upad...

Stuff by Beginner
  • 4 replies
  • 5 Helpful votes

Resolved! Multicast layer 2 flooding and cdp/vtp

Hi AllSomeone knows why Cisco switchs doesn't flood cdp/vtp packets on entire broadcast domain ?In my understanding a switch should perform flooding of Multicast packets out all port but with cdp/vtp packet it doesn't happen.Logically it is correct b...

lnrdnl78d by Beginner
  • 4 replies
  • 0 Helpful votes

Resolved! Way to forward DHCP requests w/o an 'ip helper-address'?

Hello,About 18 months ago, we stopped using VTP and switched to assigning 'allowed VLAN' to individual interfaces.  Everything has been working well.  At that time, the contractor had me turn off VTP on the core switch (default gateway) and leave VTP...

Resolved! When will %SW_MATM-4-MACFLAP_NOTIF: be generated?

Hi guys, We got this:We want to understand when the switch marks MAC  "flap"? Is there some sort of timer? It s normal for the MAC address to be learned on one port and then another, but I get it's when MAC moves very quickly back switch generates th...

Myky by Beginner
  • 2 replies
  • 0 Helpful votes

Cisco 2960S and Cisco 4912 (CatOS) FCS errors

The switches are connected by an optical patch cord. When transmitting data, errors increase on port 4912. Setting the speed and duplex on auto-negotiation or without auto-negotiation - the result is the same. The same cisco 2960S in conjunction with...

QIP Shot - Screen 008.png
ispukrsat by Beginner
  • 10 replies
  • 0 Helpful votes

Resolved! Why does pressing Ctrl+Shift-6 interrupt a command or IOS?

Hello, I would like to hear your opinion.I'm just learnig about Cisco switches and routers, and IOS (Internetwork Operating System) commands.There I learned that "to abort DNS lookups, traceroutes, pings, or to interrupt an IOS process, use Ctrl-Shif...

solc by Beginner
  • 2 replies
  • 0 Helpful votes