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All right I admit that it seems like a weird question, and keep in mind (in case you didn't understand it already by the question) I am really not a networking guy, but let me explain:
I work in an office with one (that's right) wall mounted female Ethernet port per desktop PC (about 4 total...all on different sides of the room). This port not only provides Internet access but it also provides access for all desktop PCs to the network for the rest of the building (Alas, I have no direct access to this network, nor I know anything about it).
As I am an external consultant I really don't need/care about the network resources but I do need Internet access for various tasks. I work with a laptop and there is WiFi provided by the company, but as it turns out the desk where I have to sit at is barely in range of this company provided Access Point. Signal is lost often, and I waste hours upon hours trying to get logged back on when I get dropped out. However, my desk is extremely close to one of these wall mounted ports, on which the office's boss computer is plugged into.
So I thought, "Hey, I'll just buy and hoop-up a simple little router to the wall plug and connect both my computer and the boss' computer to the router using good ol' fashioned Ethernet cables (both in a straight-through configuration). Problem solved!"
And it worked like a charm. Or so I thought.
See, the problem is that the boss computer suddenly disappeared from the network (while keeping full Internet functionality, as I did) and as my famously good luck would have it, that computer has some important resources that are needed from the rest of the team/building. Ironically, I was the only one that could see the boss computer on my network because we were connected through the router.
As the local tech support guy explained it, the boss PC could not be found on the network because it had a different IP address which wasn't recognized (these were the actual words he used). Alas, he didn't notice my little router so I unplugged it and fixed the problem for him without him even noticing it.
Maybe the simple diagram below will illustrate better the situation at hand:
Original Configuration:
____ Wall mounted Female RJ-45 Plug
| [] |
'''''' [MyLaptop(with crappy WiFi)]
||
^^^^^^^^^[BossPC]
-----------------------------------------------------------------------------------
Modified Configuration using TP-Link TL-WR740N N Wireless Router:
____ Wall mounted Female RJ-45 Plug
| [] |
'''''' ^^^^^^^^^[MyLaptop]
|| ||
|| ||---------------------------------
|| (Tp-Link TL-WR740N N Wireless Router)
^^^^^^^^^^^^^^^^^^^^ '''''''''''''''''''''''''''''''''''^^^^^^^^^^^[BossPC]
Keep in mind that for now I disabled WiFi completely while configuring the router since I don't need it.
My question is the following:
Is there a way, or a specific set of configuration settings I must use to make it so that I can use this router hard wired as shown above, but that would look "transparent" to the rest of the network? (By "transparent" I mean in a way that my Boss PC can still be viewed by everybody just like it did in the Original Configuration)
There are several ways to make it work as per your description; however, not all of the approaches would work due to the company's security infrastructure. Let's try the simple way first.
1) Disable DHCP on the TP-Link
2) Enable WIFI with your preference settings
3) Plug the wall jack to the TP-Link LAN port (not WAN)
4) Plug Boss's computer to another LAN port
5) Connect your computer to the WIFI with DHCP client enable
Note: In order for you to manage the TP-Link again, you would need to set your computer with static IP address, which must be the same range as the TP-Link IP. Example, if you TP-Link IP is 192.168.1.1 with subnet 255.255.255.0. Then you should set your IP to 192.168.1.10 with subnet 255.255.255.0.
Kindly comment on the post if this does not solve your issue.
Thanks.
Related
I run a small business network with around a 500mbit Internet connection and want to introduce an NIPS (network intrusion prevention system). I have identified SNORT or SURICATA as the software of choice (and maybe Zeek which I know less about). Perhaps with PFSense etc. TBD.
Wifi is heavily used in the business, as is standard Windows LAN-cable PCs. Currently our basic Router/Modem handles everything.
CURRENT network topology:
INTERNET ==> Existing ADSL-like Router/Modem (with DHCP + wifi) ==> Office network infrastructure etc
I want to insert a basic Linux box with 2 or four cores + 4GB of ram and a basic 1gbps network card for this SNORT/SURICATA box, before the Internet router.
I want to confirm the following is a good means to go about introducing NIPS:
DESIRED network topology:
INTERNET ==> Existing ADSL-like Router/Modem (disable wifi) ==> SNORT/SURICATA Linux Box ==> Spare Standard ADSL-like Router/Modem with DHCP + Wifi enabled ==> Office network infrastructure etc.
Question: Will this setup allow the SNORT/SURICATA box (given default settings / nothing fancy enabled) to:
Track LAN source IP address of WAN traffic, both outgoing and incoming. I.e. Torrent connection between "Local Computer LAN IP and Remote IP" -, not "Router IP and Remote IP"
Ability to login to SNORT/SURICATA box (no subnet craziness - at least not super hard to resolve problems)
Any gotchas here?
Note this is for a small business with 20 employees, not 300 etc. Conforming to every best practice is impractical at this size.
I am not keen on adding a WIFI network card to said Linux box. The reason is, in a crisis, I want to be able to unplug the snort box and connect the two routers together and immediately provide Internet to the office in case the box goes down for whatever reason (bad snort rules, hard drive dies etc). Also, router/modems need clicks to get connectivity going - I don't need to load up Putty, which would be very hard for anyone else to deal with, if I am not available.
Thanks for the help!
The setup that you are trying to accomplish can easily be done by install a pfSense box (2-4 cores and 4 GB RAM). You can choose the hardware spec from the below link:
https://docs.netgate.com/pfsense/en/latest/book/hardware/index.html
Configure suricata to run in inline IPS mode and you will be good to go. You can anytime ask for assistance while configuring suricata.
Not sure if I should ask this question here, but this is a technology community so why not.
I'm running a local network which is setup like this:
Modem -> Access Point -> Switch -> Server/5 other computers
and my problem is the 5 other computers only two computers can have access to the internet (which are connected though Ethernet).
Also, any device that's connected to my wireless network can't access the internet either.
I know it's not a problem from my ISP since two computers are connected to the internet. And I know it's not a wireless problem since my local server can be reached though the access point.
I'm not sure what is the problem since I replaced all the cables, devices, and done tons of resets.
Appreciate your help, or direction to where I can get help.
Thanks all, but my problem was that I used static IP and didn't assign more than three, two computers and a printer. completely a beginner's mistake.
I don't know if you are familiar with computer networks but I think it's a network problem. Maybe your router (modem) can provide only two IPs and that's why only two computers can connect the internet. To verify this you can check what is your IP, and what is your Subnet Mask. Type ipconfig in your cmd and give me your IP and the subnet mask to check if this is the problem or not.
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Here is the scenery. I have several buildings with same subnet IP addresses (192.168.0.0/24).
I need to secure that connection with OpenVPN.
Please assist me how can I organize VPN connection with IP network 10.10.10.0/24
example
HQ (192.168.0.0/24) - VPN 1 (10.10.10.50) --- VPN 2 (10.10.10.51) - Branch (192.168.0.0/24)
I meas assist with NAT if it will be needed or if I just connect , the C class traffic will just be passed through.
Thank you
Since you are merging two nets, you should use TAP interfaces.
TAP (as in network tap) simulates a link layer device and it operates with layer 2 packets such as Ethernet frames. TUN (as in network TUNnel) simulates a network layer device and it operates with layer 3 packets such as IP packets. TAP is used to create a network bridge, while TUN is used with routing.
This way, you will be joining the HQ network with the branch network like if you plug a (secure, pre-shared key may be ok) ethernet cable between them.
But this will likely crash both environments if they are operating now without knowing one about each other. Maybe the HQ router has the same IP as the branch one, or maybe not, but they are both acting as DHCP servers and now they will be on the same network.
Do you really need to merge both nets? I think you should consider to do some network design and let the HQ on the 192.168.0.0/24 but change the n-th branch to 192.168.n.0/24. Then you can do a TUN OpenVPN setup and route between branches and HQ in a hierachical way. It will save you some bandwith too by not spreading irrelevant broadcast traffic over the tunnel.
Thank you
Well you know, I do not have any router installed in HQ side or anywhere in network and maybe that is a big minus (and I will fix that in a time). Now I just need to secure the links between HQ and branches so the optical network provider (that provides links) could not access out data. If you have any good solution please write.
Thank you
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Bit of a random question (and I know a lot of the technology invovled is not described) but are there any networking gurus out there that can answer what is probably a simple M$ networking question that has me baffled?
Connected my laptop to the corporate network today in the same manner I do eveyday. I was allocated an IP address as per normal but unlike normal, I got no connectivity to the internet.
After a reboot and a ipconfig /release /renew the situation was the same. IP address but no connectivity.
So I called in the Techs who replaced my ethernet cable between my machine and the network port and everything sprung into life -- full connectivity restored.
My question: how did it get an IP address using that broken cable?
Most probably, your laptop assigned itself the last IP it was given by DHCP when it failed to get one from the DHCP server.
Which IP did you get? Windows computers get assigned dummy IPs when they do not get one from a DHCP server, starting with 169 if I recall correctly.
There's too many variables to keep a good educated guess. The best guess I can come up with the facts you've given is this:
The cable wasn't broken when it was initially plugged in. Maybe you were able to get an IP address before the cable broke.
As MrValdez already said, there are really to many unknowns to make a good guess. But one thing to keep in mind is, that just because one event follows another it is not necessarily caused by that event. This is also known as "Correlation does not imply causation".
It might well be, that the time to replace the cable was long enough that the real problem (router, ISP or some other thing along the path) could be solved by someone else (without knowing about your problem) or just vanished on its own.
If the cable was broken, you would get an error network "Not Connected" in the icon in the system tray. If you network connection was up, means the cable was OK.
If the cable was not of the right type, then you could have had connection up, but Ethernet negotiated to 10Mpbs/Half Duplex, which can cause a lot of pain to the use who's not aware of it, including symptoms like no connectivity, dropped packets and hence slow connection, etc.
After that, if you got an IP address beginning 169.184.X.X, that would mean that DHCP failed for whatever reason, and your laptop assigned itself a default configured IP address.
If the IP address you got was what you normally get in your LAN environment (the once with which you usually connect to the internet), then there might be some firewall issues, or something else wrong with your corporate network's router, which the Tech guys might not be too willing to share with you :-)
It's impossible to be sure but here are a few:
Network card driver: I've experienced very random things with HP laptops and ethernet cards. Usually a reboot fixes that. Green connectivity light doesn't always mean 'go', sometimes the drivers are responsible for turning the light on.
Loss of connectivity in the cable or the network plug in the compute.
Duplex negotiation problems between the switch and the computer
Maybe trying gigabit ethernet on a 4 wire cable?
If it was me I'd try an ethernet sniffer (like tcpdump or wireshark) if this happens again, see if you're getting anything in. Ping results would also be nice (to IP addresses, not hosts).
The cable and/or connectors were flaky. DHCP is done using very small UDP packets, and if enough of them are sent, eventually they'll get through. The DHCP retry mechanism is very robust, so I wouldn't be surprised if you lost 95% of the packets, and it was still enough to get an IP.
However, once you start sending larger packets for TCP/IP transactions you'll find that the 95% loss drops enough packets that even with durable TCP/IP, it's too tough to get anything useful through.
There is a lot of history here, so please bear with me.
Our home network used to be fine when we were with Comcast, but we wanted better speed and reliability, so we switched to FIOS. At that point, the Wifi connections from my Raspberry Pis stopped working. I got frustrated after a couple of weeks of trying to discover the cause of the problem and eventually put it aside.
The other day, I started to configure a new Raspberry Pi 4 that I plan to use on my new Sphero RVR. I set it up following the usual directions and the Pi connects to the Internet without problem over WiFi, but I can't ping it from my Windows 10 desktop.
So I started digging. I downloaded the Fing app onto my Pixel 3 Android phone and looked at the network. I immediately noticed that all the devices now have a 10.29.179.xxx addresses. That easily explains why I can't ping from my PC to the Raspberry Pi. They aren't in the same address space.
I did discover that I can ping the Raspberry Pi if I use the IPV6 address. I can even get PuTTY to connect using the IPv6 address, although I was unable to successfully login. I don't know what is causing the login problem, but it's probably something mundane.
I suspect that I can make my Rpi conform to the rest of the network using a static IP address, but that might cause problems if I take the robot somewhere else to demonstrate what it can do. What I would like to understand is why most of my network, using DHCP, is on the 10.x.x.x network and the Raspberry Pis seem to wind up with 192.168.1.xxx addresses.
One further wrinkle. We have two routers, the FIOS router, and a LinkSys WRT1900AC, which is the router on which WiFi is enabled.
I suspect this problem is caused by having the two routers or by something inherent in the way the Raspberry Pi interacts with DHCP.
I would like for my Raspberry Pi to configure with an IPv4 address I can use, no matter what network I am connecting it to, and I'd like to understand why this problem is happening in the first place.
Let me know what additional information you'd like to see.
* Additional Notes *
As to the comment that I have not done research. I spent a week reading through stackoverflow problems and reading up on documentation of DHCP without finding the answers to my question. I do not ask questions idley. I ask questions when I cannot find answers and need the help of people more expert than myself in the areas in which I am having trouble.
I have solved the login problem. It was a stupid password mistake.
So now I can login, over wifi, using the IPv6 address, but not with the IPv4 address.
On the FIOS router, both the 2.4 and 5GHz wifi channels are turned off.
As suggested by Ljm Dullaart, the problem was that there were two DHCP servers on the network. After I turned off the FIOS DHCP, my problems went away.