I have a small office network with windows machines and a Linux Internet access server (CentOS 5.4). For Internet access I use masquerade, so everione can access every Internet service.
I periodicali have quite big traffic from one of the hosts, but I can't figure out which one is that?
Is there any linux command which will show me the bytes/packets (or any useful infos) going to specific hosts?
I have a service, which calls other services. I need to verify that my service is hitting the right end points of the other service, since the end points of the other dependent service are specified in configs, and are different for different stages - development vs production. Is there any tool which can tell me what end points are being contacted from my host?
View 1 Replies View RelatedI have install zabbix_agent on zabbix_server, I can connect to the zabbox server from the server itself, but can't connect from other machine.
what are the steps of adding new client, I did following:
1- configure /etc/zabbix/zabbix_agent..conf, add following code...
How can i add the host on to the ZABBIX web interface?
Under Configuration->Hosts I have added the host but I don't see any report, I am no sure if server is able to see agent?
I was wondering how do you slap a packet analyzer like Wireshark somewhere between all the computers in a house and the router, so you can tell what websites are being accessed? I mean websites, specifically. I'm not trying to monitor bittorrent, IRC or other things yet - I'll get to that later. I just want to break this insanely complex task into smaller bites for now.Also, since my ISP has bandwidth caps but does not have a means for consumers to monitor total network usage, I'd like to figure out how to use Wireshark to do that as well. This, I am assuming, is easier when wireshark is running on the pipeline going into the router.
View 6 Replies View RelatedI am currently stationed overseas in Japan, and I am happy to say that I have a 100 Mbit fiber line from my service provider... I am not so happy to say that they force me to use their "CTU", which is basically a Japanese router, which limits me from receiving external connections (such as would be required to host FTP, or administer my home machines via SSH or VNC). I have tried many methods of bypassing this piece of equipment, but so far none have worked (router setup for PPPoE, DHCP, Static IP, so on). I don't think the Japanese would mind me bypassing this device, as it's really there to 'protect' me, but there's such a language barrier that I can't figure out how to tell them what I want to do.
In order to troubleshoot the problem, I would like to setup a spare computer as a hub, dumbly (Is that a word? It is for this circumstance...) passing data from one device to the other, and allowing me to watch what is being passed via Wireshark. I am pretty linux savvy, but I'm completely useless with iptables.
Here is the final product I want:
After connecting eth0 to the fiber modem and eth1 to the CTU, I want the computer to duplicate eth0's distant end MAC to eth1 and vice versa (to simulate the computer not being on the network at all), then I just want the computer to pass any data coming in on eth0 to eth1, and any data coming in on eth1 to eth0. Finally, I need to be able to read the throughput with Wireshark, but I really think that will be very simple if I can get the rest of the setup complete.
One piece of info - there is no dhcp on this link of the network, and I have no way of knowing the MAC addresses of either end before connecting them.
As an added bonus, once I've captured the handshake between the CTU and modem, if someone knows how to retransmit those packets on demand (i.e. to replace the CTU with my computer), I would be quite happy to hear about it.
I Own a netcafe and I want to limit the netspeed for some of the users on the network because some of them maybe use torrent or other ways to eat the bandwidth and the net became so slow for other users.
My task is a way to limit the net speed for some users on the network, I tried a mikrotik RouterOS but it look like a miss to install I wanted an easier way than this, I use linux or windows or any OS to make this task done please help me to do it !!
Network/IT teams often look for a monitoring tool in reaction to a problem they have on the network. They know they have a problem, but they dont know specifics. They cant see, for example, who is hogging bandwidth. So they seek a free or open source point solution to solve that one problem. But if they already know one problem is happening, it's possible theres a second or third problem which could be prevented if the IT staff knew about these issues. An alternative approach to reactive monitoring would be to implement a robust network monitoring system before a problem occurs. An NMS should enable IT staffs to identify potential problems early on and solve them before end users notice them. Is your organization using a network monitoring system? If no, why not?
View 2 Replies View RelatedThe facts are as follows:
1. I have at work a regular LAN with many PCs, each with a DNS-registered public IP. Therefore I am able to address each of these PCs by their fully-qualified names and, for instance, initiate ssh sessions to any of these computers just by typing "ssh <name_of_machine>" from a terminal.
2. Within the aforementioned LAN I have just created a private network with some clients, which access the LAN through a router (a D-link DIR-825). We have created this private network for many reasons, but most importantly because we need to guarantee that the hosts in this network will remain networked among them even if the LAN goes down for any reason (which unfortunately happens often). But we still need to have access to the hosts in the private network from the LAN.
3. I am able to define port forwarding rules in the router in order to access certain services on the private network's clients. For example. I am able to access (by ssh) hosts "H1" and "H2" on the private network from a client on the LAN by defining rules for forwarding ports "P1" and "P2" on the router's public IP to TCP port 22 on the private IPs of "H1" and "H2", respectively. Then I would access each of these hosts from the LAN by using:
>ssh -p P1 [ip.address.of.router] (for accessing H1) and >ssh -p P2 [ip.address.of.router] (for accessing H2)
4. The problem with the port forwarding approach is that it is not easily scalable. For instance, If I wanted to enable ssh access to each host in the private network, I would have to define a port forwarding rule for each machine, and then REMEMBER all these port rules when initiating a ssh session from the LAN in order to point to the right host. And the problem gets worse when considering more services in addition to ssh.
5. The ideal solution would be to be have a means for addressing each host in the private network individually, in much the same way in which I address the hosts in the LAN (which have DNS-registered names). For instance, in order to access hosts H1 and H2 as in the previous example, i would like to be able to just type
>ssh [name_of_host_H1] (for accessing H1) and >ssh [name_of_host_H2] (for accessing H2)
The bottom line:
I guess I can say that what I need is some kind of combined DNS-ing and routing that allows me to communicate with the hosts in the private network from outside of it in a transparent way.
The question is: what are any possible solutions for accomplishing this? I have searched the web and found stuff about things like VPNs, reverse-proxies and NAT servers, but I really can't understand if any of these could serve to solve my problem (BTW, isn't my router doing some sort of NAT-ing already? could I just add some DNS-ing in some way?)
I have a home PC which connects through internet via a Zyxel ADSL router. I use Fedora 14 as my one and only operating system and sometimes I am seeing the LEDs of my modem blinking very fast which means that something is downloading. I want to know which application download what on my PC. Is there any tool in Fedora that can show which application uses my network?
View 5 Replies View RelatedI want to monitor the websites that people in my network are visiting.It's a home network with various devices (PCs, phones, Ipads), and a ubuntu headless server. I'd like to install some monitoring software on the server, which would ideally provide me a list of website the devices (attempted to) connected to.Does such a software exists?? Can I control it via Webmin. Would setting my NIC in promiscuous mode affect performance?
View 1 Replies View RelatedIs it possible to have different /etc/hosts file for different network connections without having to go in and change it every time? The why: I have dyndns and port forwarding to get to my desktop. My laptop is sometimes on the same network, and sometimes not. Also, sometimes the dyndns doesn't update properly, or the outside connection is down, but I want to get to my desktop (and I'm too lazy to walk up the stairs). I'd like to be able to keep one set of bookmarks, ssh command aliases, etc. that would always get to it the fastest and most reliable way possible.
View 1 Replies View RelatedI need a script but i am not good at programming soWhat script have to do:- Every 1 minute is checking if ip address is available (ping)- if ip answers nothing happens- if ip does not answers: * file /etc/hosts is changed by one stored in /home/user/hosts* notification by xterm to restart some programIf finally ip answers file /etc/hosts is changed by one stored in /home/user2/hosts
View 6 Replies View RelatedWell, as many proxy applications, GNOME Network Proxy Preferences only allow to ignore hosts. What I want to do is exactly the opposite. I only want to use the proxy for few sites. Is it possible to define only the allowed hosts in any way?
PS: I know FoxyProxy add-on for Firefox does this, but 1)I don't use Firefox and 2)I want the proxy settings system wide not only for browser.
Any easy to install/configure network/server monitoring tool? PLease note I'm looking for something of little lightweight here (Not something like zenoss) But I'd still like to get performance graphs and event notifying alerts. Also note this is to monitor less than 50 servers and perhaps a firewall or 2.
View 2 Replies View RelatedI have a third party program (tightvnc) which I want to monitor and detect if it loses a connection with a client. I don't care if the client has the program open but isn't doing anything with it, I only want to know if the actual TCP connection is lost.
Since TCP takes forever to die on it's own I was thinking the best way to detect if a connection is lost is by bandwidth the bandwidth on the tcp port allocated to the VNC connection. Are there any tools built in to redhat (RHEL 5.2) which I could use to do this? Since I don't have full control of the operating system I would prefer to use built in tools rather then trying to get a new tool installed.
Problem:Your company network has internal only hosts / websites with names that end in .local, e.g.Your freshly installed Ubuntu machine works fine on the network, has internet access, etc. but cannot connect to these particular systems.Testing DNS with tools like dig / nslookup works fine, but normal name resolution with ping / telnet / browsers does not work.Solution:1. Open a terminal window2. Enter the command sudo nano /etc/nsswitch.conf3. Change the following line:hosts: files mdns4_minimal [notfound=RETURN] dns mdns4to this:hosts: files dns4. Press Ctrl-X, Y, Enter to saveExplanation:Ubuntu ships configured to do name lookups for self-configuring networks, based on the AppleTalk / mDNS / Bonjour protocol. In the configuration shipped for the resolver, this protocol is considered the final aurhority for the ".local" top level domain, and DNS will not be checked. The above configuration change eliminates this and restricts lookups to (a) /etc/hosts file, followed by (b) DNS
View 1 Replies View RelatedI just installed open Suse 11.3, and I cannot SSH my school. Upon further investigation I could not even ping any machines outside my local area network. Ironically I could nmap machines outside my local area network.
View 4 Replies View Relatedsince a few weeks I have a problem connecting to other hosts when I'm using another wireless network, which has a different DNS IP than I have in my network. I have to change /etc/resolv.conf to change the nameserver. Can NetworkManager control the nameserver? If yes, how?
View 3 Replies View RelatedPlease suggest few best linux networking tools which are desciptive. That is to monitor local network PC whether its linux or windows pc.
View 2 Replies View RelatedI'm trying to use ssh-keyscan to get some known_host file population going on, but I have a ton of hosts I want to scan, all with multiple aliases in /etc/hosts. Is there a way to use my current /etc/hosts file to do an ssh-keyscan instead of making a special list of hosts that (from what I've read) ssh-keyscan needs?
View 2 Replies View RelatedI just wanted to use a network bandwidth usage monitoring application. Scenario: I am using an EV-DO based USB broadband modem with a limited GB plan. For additional data usage they charge per MB. Currently I use either wvdial (mostly) or pon to start the connection. So if there is any network monitoring application which could log time used and data used for the session, it would be great. Actually debian has too many different network monitoring applications, But I am not sure which one suits well for this purpose.
View 5 Replies View RelatedI am currently running a 64-bit Fedora 14 server which hosts a game server, a voice server, and remote desktop functionality, each on a distinct TCP port. I am currently using the built-in firewall to deny all traffic other than ICMP ping/pong and TCP traffic on those specific ports.I am looking for a graphical application which will let me monitor any connections being made to my server in order to keep an eye out for possible security concerns. To be more specific, I'd like to be able to see the source IP addresses, TCP/UDP ports, and individual bandwidth in use by external connections being made to the server, along with any other information that might be helpful in identifying a possible intrusion attempt.
View 3 Replies View RelatedMy question is simple - is there any linux app or applet which is able to show (monitor) incoming and outgoing connections assuming it's a direct internet access? I was using a firewall on a system off Redmont which was able to show every connection, listening ports of services if some were opened etc.
View 1 Replies View RelatedIs there a program that monitors and displays 'who' is on your wireless Internet signal that one may not be aware of? Like, the ability to see when someone that you don't know is accessing your locked wireless?
View 9 Replies View RelatedI use network Manager to connect to wireless broadband on Fedora 12.Are there any tools that can provide me logs about connection times, bandwidth monitoring etc.Basically, I need logs like what kppp provides with accounting.
I can use kppp to connect and get the logs I need but I want to connect to the network as soon as I plug it in - Only Network Manager allows this.
I have a debian squeeze box with dual NICs that I'm trying to configure with two virtual hosts. I'd like to have one of these machines act as a router for the 2nd NIC so I can plug in a switch and have a separate subnet.
Something like:
- Openwrt router 192.168.1.1 (firewall/vpn/stats for 192.168.1.0/24 domain)
- KVM machine with 2 NICs (192.168.1.2)
- Virtual machine #1 has a fixed IP of 192.168.1.3 (virtual nic)
- Virtual machine #2 has a fixed IP of 192.168.1.4 (virtual nic) but also controls the 2nd nic and routes 192.168.80.0/24
I'd like to use the 192.168.80.0/24 network for testing equipment without poisoning my existing network.
since upgrade to suse 11.3 every time I reboot pc the file /etc/hosts is reset to default value. I am a web developer so I need to put in there my aliases for 127.0.0.1. It is annoying to do it again and again. Luckily, I don't restart my system very often but still I would like to avoid that.What should I do to stop this resetting? Or is there another place in 11.3 where should I put my entries?
View 9 Replies View RelatedI have some settings within hosts file of my Windows Vista. It helps me to bypass some limitation and get online better. I would like to migrate some settings to openSUSE 11.4.Is there anyone who knows how can I tune my openSUSE?FYI, setting of hosts file is lines of <IP Address> <Spaces OR Tabs> <URL OR Alias>
View 4 Replies View RelatedI have a box which I want to make a Samba PDC opensuse 11.3 server, but it doesn't have monitor nor keyboard during normal use. After a standard installation with keyboard and screen, I will have to remove the screen and the keyboard for lake of space. Are there ways to monitor this linux server through my laptop so it act as the screen and the keyboard of the linux server? At any times, the laptop is running desktop opensuse 11.3 or windows XP.
View 9 Replies View RelatedI was reading a magazine article today which was a discussion of internet detective work for tracking down ip addresses which attempt an ssh login to your machine. I have never really paid much attention to network security since I only run a small home network. I have WPA encryption and a firewall on my router. But while reading this article, I remembered that I myself has seen log files in the past that inidicated someone somewhere had attempted to log into my machine (attempts all failed). This had happened a few times, but I never really considered it a threat.
But, the more I read about home computers becoming "zombies" for criminals, I guess I am getting a little paranoid in my old age, particularly since my wife does quite a bit of business on the net with credit cards. I have four computers connected to the net and each other on this network, and would like to be able to easily detect attempted log ins and deal with them quickly.
So my reason for posting is to ask if someone could recommend a novice-friendly application for monitoring traffic to check this intermittently. I have read bodhi.zazen's excellent tutorial on snort, but I it appears to be written for large lan's or web servers and is over-kill for a small home network.