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Questions tagged [switch]

For questions about network switches, the term commonly refers to a multi-port network bridge that processes and routes data at the data link layer (layer 2) of the OSI model.

2
votes
1answer
28 views

Question about Ubiquiti Edgemax switch syntax and VLANs

I've been beating myself over the head with a keyboard trying to figure this out. I'm used to switchport syntax on Adtran and Cisco switches, but I've got this situation with a Ubiquiti EdgeSwitch 48 ...
0
votes
0answers
11 views

setting up switch to fios gateway [on hold]

I have a fios gateway router, I connected a switch to one of the ports, and connected some devices to that switch. Computer,and a PS4. These devices connect to the internet and work fine. However ...
1
vote
0answers
21 views

Why Korenix Switches hang up SSH so often? [on hold]

Does anybody know, why Korenix Switches hang up SSH so often? And then, you have to restart the switch each time, that happen. On HP Switch there is no problem with that SSH. If anyone has any ...
0
votes
1answer
31 views

1 switch handling several servers or several switches handling a server each?

Which of those two approaches are better for a more stable network? I was thinking 1 switch handling several servers so that other switches are able to handle other devices such as a desktop PC or ...
0
votes
0answers
14 views

Can't Find Latest Firmware for CiscoLinksys SLM2048 Switch [on hold]

How can I get get the latest firmware on a obsolete Cisco switch? Specifically, even though the CiscoLinksys SLM2048 is retired equipment, I have one that still works well, and I'd like to install ...
3
votes
1answer
22 views

SG3xx Password Reset/Recovery

Trying to reset a password for a number of switches I have. Didn't save the text file I had jotted it down in....of course. Connected via serial, but cannot seem to locate any concise info on ...
4
votes
1answer
56 views

Same Vlan Name / ID on different switches network subnet same or different?

I have several switches (some on same floor and another on other floors) all connected to core layer 3 switches through trunk links. One of the vlan id / name is repeated along the switches. May I ...
-2
votes
2answers
58 views

is it ideal for a network that abandon the use of L2 switch?

I'm thinking about minimizing network hardware while optimizing network topology for company. If a company has unlimited(or very high) budget to build an ideal network for internal use(traditional ...
1
vote
1answer
39 views

Cisco nexus 9396PX TX output discard on 40G interface without link congestion

We have cisco nexus 9396PX with N9K-M12PQ module (12x40G Interface), We have 8x10G L3 LACP bonded connectivity with our ISP and so far so good no issue at all. but recently we migrated that LACP LAg ...
6
votes
1answer
1k views

Cisco 3750X Power Cable

I received a Cisco 3750X the other day. I went to go plug it in for testing and found that the standard three prong female power connector is no longer compatible with the power supply. Cisco has ...
2
votes
1answer
58 views

Do unmanaged switches honour QoS priorities set by managed switches?

Details about the devices We have a 24 port NETGEAR managed POE switch that has QoS capabilities. We also have the following unmanaged switches, 24 port Cisco POE, 48 port Cisco, 48 port NETGEAR, ...
5
votes
2answers
46 views

What's the `line protocol` and `Link`?

When I show a switch interface information, there are line protocol and Link: Switch-A(config-if)# show interface gigabitethernet 0/3 Gi0/3 up, line protocol is up (connected) Bridge Port Type: ...
1
vote
0answers
20 views

How can I filter the exact interface in huawei switch?

How can I filter the exact interface in huawei switch? you see when I use the include GigabitEthernet0/0/1 to filter, there will get many GigabitEthernet0/0/1* interfaces: <Z178A>dis ...
3
votes
2answers
34 views

Firmware Compatibility with 15.x IOS versions

I have a Cisco switch stack with both PoE and non-PoE switches as members. Is there any compatibility issues with the firmware version 15.0.2-SE11 between the following devices? 1x Cisco WS-C3750G-...
7
votes
2answers
433 views

OSPF increase bandwidth with load-balancing

This is my current setup where i have 40Gbps links between all 4 switches running OSPF using L3 links between them but now i want to double my bandwidth between switches so i am planning to add (...
4
votes
1answer
382 views

Why would a switch ever send an ARP request for a MAC address when it can just wait for the first packet to be received from a device?

I've been reading 'Windows Networking Fundamentals' and in that book it says that a switch can learn what MAC address is associated with a particular port when the connected device makes its first ...
3
votes
0answers
36 views

Cisco nexus 9396 rebooted with reason xbar_client

Today my one of cisco nexus 9396PX switch got rebooted and this is what i found, based on following logs what could be wrong? We don't have Cisco support for this switch, trying to see if i can get ...
2
votes
1answer
18 views

Shoretel ST1D Switch not accepting assigned IP

After configuring a Shortel ST1D switch, I connected the LAN1 Port from Shoretel ST1D to my Cisco 4507R switch. I attempted to ping the IP that I set specifically on the ST1D switch and I wasn't able ...
1
vote
0answers
36 views

Cisco nexus spanning-tree logging to syslog

I am trying to send my spanning-tree events to remote syslog but somehow it doesn't work, This is what i have in my config. N3K# sh run | grep logg logging level spanning-tree 7 logging server 172.29....
2
votes
1answer
58 views

spanning-tree port type edge trunk on port-channel vs physical interface

If i configure spanning-tree port type edge trunk on physical interface instead of port-channel does that work? Or i have to do spanning-tree port type edge trunk on port-channel ? Example: ...
1
vote
1answer
157 views

Flooding vs Unknown Unicast Flooding

Can someone clarify what is the difference between Flooding and Unknown Unicast Flooding? Is it the same thing or it contains different meaning? I'm aware that Flooding happens when a switch ...
1
vote
1answer
19 views

Cisco swtich stacked NTP configure

I have two cisco switches (WS-C3850-12XS-E) stacked by stack cable. I want to configure ntp on them. How to configure ntp on those about time synchronization?
0
votes
1answer
78 views

Does vPC peer-gateway cause unicast flooding

This is my network topology where I have SW-1 is configured for HSRP for multiple VLANs, SW-2 & SW-3 connected to SW-1 using vPC. Last few month I am dealing with this unicast flooding where ...
3
votes
3answers
388 views

Collision domain question

I'm studying for my CCENT exam, and not quite sure why the book (official Cisco) says that there are 5 collision domains in this example. Isn't it supposed to be 4? The hub on the left, the hub in the ...
1
vote
1answer
49 views

No MAC address table shown on Cisco switch

I'm studying CCNA1. following netacad course notes and sending "show mac address-table" to a switch (in packet tracer) I should get a list of the available MAC addresses. I only get the table header ...
2
votes
1answer
65 views

VTP does not update VLANs in switch

Switch 1 will be server and Switch 4 will be Client! Switch 1 configuration S1#show run Building configuration... Current configuration : 1451 bytes ! version 16.3.2 no service ...
0
votes
0answers
10 views

Managed / Unmanaged Switch [duplicate]

This is a basic question, But can someone clearly state what is the difference between managed and unmanaged switch? Also, do managed switches maintain their own routing table?
1
vote
1answer
51 views

Configure Nexus N9K-C93180YC-EX

I am configuring a switch for the 1st time (Cisco Nexus N9000 Switch) to do some server performance testing in my lab. I have the serial console working and can log into the switch and run commands. ...
1
vote
1answer
43 views

Connecting networks from different states [closed]

Is it possible to connect 5 networks together using one router as a central component even if the networks aren't close to each other? An example would be 2 networks in Houston and 1 in Dallas Texas, ...
6
votes
6answers
1k views

Do I need to protect SFP ports and optics from dust/contaminants? If so, how?

I have a used switch with some SFP ports and some SFP modules installed, which I don't use. All new switches come with little rubbery bungs that block up unused SFP ports, but since this old procurve ...
5
votes
1answer
46 views

Non-HP transceiver and HP switch

Does a non-HP single-mode transceiver work in a HP switch, and does a non-HP single-mode transceiver communicate with a single-mode HP transceiver?
2
votes
2answers
76 views

Obtaining packet switch-port information via a mirrored port?

When sampling a mirrored port of a switch, is there any means of determining the switch-port information of the packet? Since Ethernet packets do not contain this information, I assume the answer is ...
3
votes
1answer
150 views

Strange flooding during installing new switch in network

This is very strange issue i am noticing. In our datacenter we have every switch in rack has cisco vPC configured in short whole datacenter running vPC so there is no loop for spanning-tree anywhere ...
2
votes
1answer
64 views

Duplex mismatch between a Fast Ethernet router and Gigabit Ethernet switch with auto negotiation

i am connecting c3745 router on fast ethernet 0/0 interface with a IOSvL2 switch on gigabit ethernet 0/1 on GNS3. i have set the negotiation on the switch to auto for all interfaces on the switch. ...
0
votes
1answer
32 views

How does Kismet find WIRED devices when scanning Wi-Fi? [closed]

In an effort to better secure my Wi-Fi network by finding its weaknesses and mitigating them, I have employed the use of Kismet, a well known Wi-Fi security scanning tool. When I use Kismet to scan ...
2
votes
3answers
76 views

Is it possible that two servers were configured with the same ip under the same switch

I have two physical servers, their configuration as following: ServerI: IPADDR=10.1.1.5 NETMASk=255.255.255.0 ServerII: IPADDR=10.1.1.5 (Same IP) NETMASk=255.255.0.0 (different NETMASK) Because of ...
3
votes
2answers
38 views

HP switch “No untagged port”

A network engineer showed me the show vlan output of an HP switch. I know tagged ports are trunk and untagged ports are access in Cisco terms. But can anyone explain the "no untagged port"? How is ...
22
votes
8answers
4k views

Why can't devices on different VLANs, but on the same subnet, communicate?

I have a question about switching. I have two devices connected to a switch with IP addresses 192.168.5.20 and 192.168.5.10. Both devices have the same prefix, /24. That means they are on the same ...
4
votes
1answer
92 views

Cisco 2960L and ISR 4331 throttled WAN speeds

I have tried finding a solution to this issue and the closest I have found thus far can be found here. https://www.reddit.com/r/networking/comments/8f2sn0/throughput_limited_by_cisco_2960_switch/ My ...
1
vote
2answers
46 views

How does pfSense control network traffic when plugged into a switch?

I apologize for this n00b question, but I'm trying to learn networking to help at a non-profit where the old IT guy is no longer there. They have several Cisco switches and one pfSense instance that ...
1
vote
1answer
40 views

Can't install OS on S6000-ON

I have a Dell Networking S6000-ON. I'm trying to install an OS with ONIE but am running into an issue with the EEROM TLV info. Using some of the onie-syseeprom commands came back with this: ONIE-...
0
votes
0answers
37 views

sflow configuration Cisco Nexus 9396PQ

We have Cisco a Nexus switch with M12PQ 12x40G GEM expansion card. Today when i enabled sflow on one of 40G interface i got following error: # sflow data-source interface e2/12 In order to enable ...
0
votes
1answer
70 views

Is there a MTBF related to port linking?

During a firmware upgrade, I've noticed one problem: An equipment keeps linking/unlinking on a specific port of a PowerConnect 3548(stp portfast, switchport access mode). I've contacted the local ...
0
votes
0answers
29 views

Why does my 1921 Router not bring up its interfaces?

I have the 'no shut' command entered on both interfaces. They work when I enter the command. I copy run start 'wr' Power was cycled for the Router, Switch (3560x-24), Cable modem and AP. They were ...
0
votes
1answer
59 views

cisco switch iOS running into problem

I updated Cisco 2960x iOS, but when it started to operate I encountered this error. "Mar 25 12:02:19.878: %ILET-1-AUTHENTICATION_FAIL: This Switch may not have been manufactured by Cisco or with ...
0
votes
1answer
49 views

Arp Cache Timeout [closed]

I'm trying to poll the arp table from a backbone switch but i want to understand which records are up. I just want to know if there is a specific time for the switch to keep a record on the arp table ...
1
vote
1answer
22 views

Can a hub be used for sniffing traffic from a device?

My intention is to analyze all network traffic which is coming to and originating from a network connected device I have. From the configurations of the device I am able to proxy all the HTTP traffic ...
1
vote
0answers
41 views

Colocation network setup - 2 switches with each 1 uplink - redundant configuration question

I have a question about the network configuration when connecting 2 switches in a colocation rack via 2 uplinks (1 uplink to each switch) to 2 other switches of the datacenter itself. My topology ...
1
vote
0answers
35 views

DHCP over Frame Relay [closed]

I have two co-operate buildings. Building A is connected to building B via frame relay. Building A has the main switch server (with VLAN info) and a DHCP server. I need Building B devices to receive ...
3
votes
1answer
27 views

Access and uplinks ports QoS Queuing model

On an access switch, does the uplinks egress QoS Queuing model (multiple traffic classes and bandwidth reservation), should be different than the access ports egress Queuing model ? Is there a sense ...