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1answer
75 views

Layer 2 and Layer 3 traffic with one cable

Hers the topology. L2 switch L3 switch Router There are 2 VLANs. One VLAN ends on the L3 switch 1 VLAN on the router. Here is the question. Can i connect the L3 switch and the router with just 1 ...
1
vote
1answer
33 views

Assign a new public and static IP to a router behind my main router [closed]

What can you suggest to bring a second public and static IPv4 so I can configure my WAN-A interfase with my primary and an additional secondary IP settings so I can route all the traffic from the ...
0
votes
2answers
92 views

Which physical layers are part of PROFINET?

I understand that Profinet builds on Ethernet, but I am not quite sure how. Ethernet has a lot of different standards for the physical layer, eg 10Base2 (coaxial, 10 Mbit/s), 100Base-TX (twisted ...
1
vote
2answers
33 views

How to configure snat between 2 private networks having different nat pools?

Hi, i'm having some problems with the current configuration i have on this network. I have two nat pools one for the blue square routers, and another for the yellow ones. And i'm using snat to have a ...
0
votes
1answer
22 views

Which path will frames prefer in this setup? [closed]

So I recently installed a long rj45 cable to replace the powerline adapter I was using. I'm keeping the PLA in place as a failover but wanted to know if I will need to swap the connection by hand to ...
0
votes
2answers
84 views

Troubles wiring two network rooms with optical fiber and SFP-enabled switches

I'm in charge of the new network installation in the new office of my company, and I have troubles wiring two network rooms (one for servers and incoming internet and the other one for wiring closets) ...
0
votes
2answers
49 views

Confusions regarding byte and bit ordering of Ethernet Frame

I understand the concept of Endianess regarding numbers because there the bit significance is well defined. But when applied to things like Ethernet frame or Mac address, things are so clear to me, ...
0
votes
0answers
19 views

factory reset without fail nvram

My problem is to reset the NVRAM without fail the flash memory. I try to recover password from NORTEL CORE SWITCH-8310 old model. I try to enter the monitor mode but I fail. PLZ suggest HOW to process ...
22
votes
3answers
9k views

What is “industrial ethernet”?

When a teacher introduced it to us he gave the impression that it specifically covers some Siemens technology; that it's even a Siemens trademark. I believe the term covers something more general, ...
2
votes
0answers
49 views

Route Reflector not reflecting BGP-LU (Labelled Unicast) prefixes

I was reading about the Inter-AS MPLS VPN Option C from book ' MPLS in the SDN Era' . In it , the author establishes the BGP-LU peering between PEs and ASBRs and between RR and ASBR only.No BGP-LU ...
-1
votes
1answer
31 views

ccna: Collision domain vs broadcast domain [closed]

I am currently preparing for CCNA I have a screenshot of CCNA online test. I don't remember if I got it right or not. I think there are 2 broadcast domain (circle with hand on the picture) and 5 ...
0
votes
1answer
62 views

Weird Wireshark protocol list (eth:ethertype:ip:data where is the “udp”?)

I am capturing incoming and outgoing WAN to LAN data at a particular host on my LAN (i.e., the one actually receiving/sending the data). Sometimes I get anomalous captured frames that are missing the ...
4
votes
1answer
79 views

How do ARP requests work

So I may have a stupid question that mainly comes from me getting weird results to say the least while experimenting. I'm a bit unsure how do ARP requests work. For example how can I arp my entire ...
0
votes
0answers
23 views

How to implement port security in SDN using pox controller and ovs?

How can I defend against DHCP starvation attacks or MAC spoofing in an SDN environment?
0
votes
1answer
35 views

RDP on IPV6 using DS-Lite-Tunnel [closed]

I am trying to access one of my PCs from and external network using RDP on port 3389. After realizing my ISP uses DS-Lite-Tunnel I gave up ipv4 and focusing on ipv6. So far the only way I managed ...
0
votes
0answers
25 views

GNS3 Not working after upgrading ubuntu 19.04

I upgraded Ubuntu 18.04 to 19.04 and GNS3 stoped starting. in CMD this Message appears sudo gns3 Fail update installation: No module named 'sip' Can't import Qt modules: Qt and/or PyQt is probably ...
1
vote
0answers
37 views

How can I disable TLS on my openvpn server? [closed]

I am using PiVPN and set up an openvpn server. Myself and a coworker can connect to the vpn remotely with the generated .ovpn files we imported into openvpn clients. I tried creating a .p12 ...
0
votes
0answers
24 views

Has anyone successfully deployed WLC 8.3+ anchored wlan with PSK and CWA?

There seems to be something broken with Cisco WLC 8.3.140 and 143. 8.3 was the first AireOS release training to add MAC Filtering (CWA) and PSK. ISE is serving as the RADIUS server (v2.2). I can get ...
0
votes
0answers
25 views

unable to capture http request on loopback using wireshark

I am running apache2 webserver on my machine. When I try to access a webpage locally through a webbrowser as locahost/index.html then i dont see any packets having protocol http in the capture ...
0
votes
1answer
36 views

bind to specific address

What does bind to address 192.168.1.4 mean? I have to come to know that if an application bind to 0.0.0.0 then it means listen on all interface but it doesn't make much sense to me can someone ...
0
votes
0answers
14 views

Connect a Multicast sparse-dense deployment with a sparse deployment

I am working on a task that involves deploying a new network in parallel to the existing network. As a part of this deployment we are going to cross connect the two networks so that it will allow for ...
1
vote
0answers
44 views

Is this wireshark capture showing any issue?

I used Wireshark to capture the packets bellow: ... 350 18.942762436 d0:07:ca:0b:63:0c -> Broadcast ARP 60 Who has 13.210.32.75? Tell 13.210.32.78 351 18.947224197 d0:07:ca:0b:63:0c -> ...
0
votes
1answer
22 views

Whether the anycast nodes can not in the same AS, and whether the different AS can pronounce the same IP segment?

The Anycast realize is through annunciate the same IP address in the different node using BGP protocol. you see the Server A and Server B use the BGP annunciate the same IP address 10.0.0.1. There ...
1
vote
1answer
43 views

How to do port mirroring in Juniper EX2200 switch

I am using Juniper EX2200 switch, one of the connected System generating lot of unwanted traffic ( varying from 10 Mb to 25 Mb upload traffic). I wanted to analyse those traffic using port mirroring ...
1
vote
1answer
62 views

Dropping packets between router and firewall without firewall rule

I have a user that is trying to access his company network resources on his home network. He is able to access SMB shares and other resources, but he is unable to access their AS400 on any computer in ...
2
votes
0answers
27 views

Whether all the edge router has the CERT `Advisory CA-1996-21` process up? [closed]

Whether all the edge router has the CERT Advisory CA-1996-21 process up? We know after the DDoS attack of Panix at 1996.9, the CERT release the CA-1996-21 announcement. it is take effect of edge ...
1
vote
2answers
47 views

How to configure NAT between 2 private network ? CISCO routers

If anyone can help with configurations it will be helpful
1
vote
1answer
33 views

Static routing using 2 routers and 1 multi-layered switch

I'm trying to configure a static route between two routers and a layer 3 switch as follows - Router 0 interface FastEthernet0/0 ip address 172.17.10.1 255.255.255.252 duplex auto speed auto ! ...
0
votes
0answers
15 views

How do I find the number of IP addresses between two given IP addresses? [duplicate]

How would I find the number of IP addresses from 224.65.0.0 to 225.127.255.255?
0
votes
1answer
39 views

Configure RIP routing for 2 routers and 1 L3 switch

I'm trying to configure RIP routing between the 2 routers and 1 L3 Switch. My Router0 configuration - f0/0 = 172.17.10.1 f0/1 = 172.16.10.11 Router#sh run Building configuration... Current ...
1
vote
0answers
16 views

Multiple connections to a webinar and modem went down [closed]

I've kind of inherited the role of sysadmin at my company, even though I never went to school for something like that, and I really don't know what I am doing (haha). Long story short: yesterday ...
2
votes
2answers
53 views

wifi and vlans problems

I was given the task to come up with network design to change the existing one that we have since we are running a single network in the company with no VLANs in place to separate de departments. On ...
2
votes
1answer
35 views

How to see vlan access-map matches?

I have created vlan access-map in my Cisco Catalyst 2960X to block https traffic: ip access-list extended no443 permit tcp any any eq 443 vlan access-map block443 10 match ip address no443 action ...
1
vote
0answers
45 views

What is UDP traffic on port 80 and 1024? [closed]

I am currently investigating a set of anonymized passive Internet traces from a monitor in New York. There I am seeing a lot of traffic on UDP ports 80 and 1024, and I was wondering what that could be....
0
votes
0answers
18 views

Dell N-Series SNMP, Mac address table

I have already tried this: Using SNMP to retrieve the ARP and mac-address tables from a switch and various other approaches. I'm trying to do a walk on my Dell N2048P to retrieve all active mac-...
0
votes
2answers
71 views

Why can't we have duplicated IPs?

This may be a really dumb question, but I like to turn upside down what I already know sometimes, that way I can learn more. For example, given a network 192.168.0.0/24, I have a device inside with ...
1
vote
0answers
33 views

Can you create an open LTE network?

Being an ex-politician, I've had to discuss "free city-wide Wi-Fi" many times. What I've always been thinking is, why don't we just have free 3G/4G in the city? Is it possible to have an "open" LTE ...
1
vote
2answers
28 views

How many public static ips do one need if a PC is behind a wireless router?

If a PC is connected to internet through a wireless router. How many public static ips do one got to get from the ISP. Do the router and PC both require one static IP. What if I want to add more PC ...
0
votes
2answers
62 views

Two NICs - IP address conflict between 2 networks?

I have a Windows PC with 2 NICs; one NIC connects this machine to the local LAN while the other NIC connects this machine directly to an X-ray machine (which I'll call the RayLAN). So my question is ...
0
votes
1answer
18 views

LAN to LAN Connectivity of Moxa routers

I am with background of DevOps and to optimize stuff in office i am assigned a networking task with not much experience of networking. My scenario is like below I have two moxa (EDR-810) routers ...
0
votes
2answers
84 views

How to ping router from L3 switch

I am stuck in that that switch can't ping router and router can't ping switch. How to fix that ? I tried so much variants but them didn't help me Actually router must do static routing, that i am ...
0
votes
0answers
18 views

Are there NATs which will block any further incoming packets from a peer after rejecting first one?

I'm attempting to test udp hole punching. Right now I'm simply testing how my computer reacts behind a router. If I send a udp packet from my computer to a server, it can reply back on the same port ...
0
votes
1answer
34 views

Multicast in enterprise network

Once I have heard from a professional that multicast is forbidden (or not suggested or not allowed) in enterprise networks from 2014. (He referenced to a standard or recommendation document or ...
0
votes
1answer
38 views

Wireshark captures TCP packet with no flag [closed]

In our network, I captured a TCP packet by Wireshark that has no flag set. What's that mean? Is it normal?
0
votes
2answers
48 views

How to cascade two routers [closed]

When I connect two (Zyxel) routers in a cascade configuration, I don't know how to set the right address on the Lan Interface between the outer router (the one on the top of the diagram) and the inner....
0
votes
0answers
20 views

Loop-prevention measures on BGP-signalled VPLS

I have a project to configure a BGP-signalled VPLS overlay for an MPLS network. I will multihome the VPLS to a switching fabric via 2 PEs for redundancy. I understand that VPLS split-horizon behavior ...
-1
votes
1answer
35 views

GRE over IPSec Transport vs. Tunnel Mode

I have a misunderstanding, in this article, Figure 4-9, in Transport Mode, first header (IPsec Hdr), is correct? Should not be GRE IP Hdr? https://www.cisco.com/c/en/us/td/docs/solutions/Enterprise/...
4
votes
1answer
56 views

Switch updating - Cisco Prime

I'm tasked with mass updating of our Cisco switches via Cisco Prime. Is it possible for the update to fail? Can the switch 'hang' in reboot loop? What if I tell Cisco prime to backup running image? ...
2
votes
1answer
33 views

Using Extended ACL on destination instead of source

In the diagram we are required to block all the external user ping requests to the sever. For this I have created the following ACL on R1: access-list 105 deny icmp any any echo access-list 105 ...
1
vote
2answers
66 views

Cisco 3750X Switch stack best practices

I have a stack of 5 Cisco 3750Xs. I am debating between taking all my servers and putting them on one of the 5 switches, or distributing them over the first few ports of all 5 switches? All of the ...

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