I have ssh running on port 22 and that is the only thing I want in/out of this particular box (ssh, scp).But when I use iptables to set the default policies for INPUT, FORWARD, and OUTPUT to DROP and then allow 22:
iptables -I INPUT -p tcp --dport 22 -j ACCEPT
iptables -I OUTPUT -p tcp --dport 22 -j ACCEPT
ssh stops working.
I am a under-graduate student. my prof has implemented an adhoc protocol and simulated it on some network simulation software and it worked out of box. She want to implement it on real world unix/linux systems. i am sure it is possible, but i dont know where to start from.
View 5 Replies View RelatedHow to implement Network Protocols.
View 1 Replies View RelatedI have setup NTOP on Centos 5.5 and am not seeing traffic that I am supposed to be seeing. We have a product that uses many different services including ssh. I have this system as a target on mirrored ports but am not seeing any ssh connections or activity when I look at the host machine that is connected to the target ssh client and vice versa. When I look under TCP/UDP Service/Port Usage it is not displaying all the services that are being used especially SSH. What could it be?
View 5 Replies View RelatedWill ipv6 use the same routing protocols as v4?....such as OSPF?
View 2 Replies View RelatedI am new to using wireshark and I've been browsing around the packets it a bit. I figured I'd try and use it to cut into a protocol that isn't documented, that I can find, but doesn't seem particularly secure. I tried cutting into a protocol and I turned _everything_ off, but wireshark was still picking up packets left right and centre. So I decided to stop the internet daemon and still, packets were being sent over the internet. So I decided to pick some of the IPs and do a reverse look-up. Each and every one of the IPs are of Russian origin or close.
I'm under the impression that these are unwanted packets. I've also noticed that they are sending data from the same port: 32165. Another thing I noticed while doing reverse look-ups is a lot of these IPs are hit in 'Spam & Open Relay Blocking System' and 'Project Honey Pot' which seem to be spam blockers and trackers. What I should do or what I should investigate? The reverse look-ups are only providing me with the ISP which 'owns' the IP block the IP is apart of. They are from various ISPs every time.
I have project which need to stream audio to multiple remotely connected devices on internet.the best protocol for streaming with minimum or no audio distortion.
View 1 Replies View RelatedI'm writting an app for desktop and embedded linux and I need to get information about the multiserial port, and I need to know which port is been used (by a printer, por example).The multiserial I'm using is an Altera Corporation Device 0004, and I just need to tell how many ports are there and how many is been used.
View 3 Replies View RelatedA few months ago I installed Ubuntu 9.10 on my girlfriends laptop, on her request, as she didn't like Windows any more. Since then the internet connection periodically slows down due to too many open ports/connections. Always when this happens I call our ISP and usually there are around 80-200(!) active connections to various IP's.
She is not downloading torrents or anything.
She only uses Firefox and a few open tabs as people do.
Skype is open.
Wireless internet connection.
I am thinking either Ubuntu is updating more or less constantly or the ports/connections aren't closed "after use".
Does any body know how to enable ports in ubuntu 10.04?
View 2 Replies View RelatedI'm trying to VPN in somewhere and it doesn't like any outbound connections. I'm doing this for RDP, so can I somehow restrict the VPN connection to only be using the RDP port?
View 1 Replies View RelatedI dont know how, but somehow all the ports on my comp appear to be blocked except for 24, for ssh and 5900 unknown. I can connect to the network, but as far as I can tell, I'm powerless to do anything. No webpages load, I'm typing this on my phone.
View 1 Replies View RelatedI was following the directions over on the page How to watch Hulu overseas without a proxy server and got to the section about blocking ports, which I need to block port 1935. I figured this would be easy, as the mac instructions are
Code:
sudo ipfw add 0 deny tcp from any to any 1935
sudo ipfw add 0 deny udp from any to any 1935
and the Windows instructions are practically a book in itself. Since this page was lacking instructions on how to do it in Ubuntu, and ipfw seemingly doesn't exist in Ubuntu, how do I block the ports
I'm trying to open my ports all the way, but for some reason, I am unable to do so. I've forwarded the ports I want open in my router (I switched between two routers to make sure), I made exceptions in Firestarter, and I even added UFW rules, but when I use pretty much any and every port checking tool out there, the ports eithere back stealthed or closed.I'm not a complete noob, and I'm not an expert, but I'm p sure I'm doing everything right, seeing as there isn't much to screw up.The reason I'm trying to fully open these ports is because I'm getting this dumb 'No Incoming Connections
View 3 Replies View RelatedDoes Ubuntu come with a firewall preinstalled and running? I need to open port 9997 - how would I got about doing this?
View 2 Replies View RelatedI have been running Ubuntu 10.10 and have found that at any time I am connected to the Internet that I will randomly see high port numbers open when doing a port scan on my computer all are in the unknown listings with five digit numbers so I don't know what is going on or who is using them. Please check your system to see if you are having the same thing happen by using network tools and filling in your local ip address in the port scan tab. If you shut down your Ethernet interface and run port scans the high ports are no longer open. this will at least keep whoever is using your ports at bay when you are not using the net.
View 4 Replies View RelatedMy first one is the network: Our routers' ethernet ports are all in use and I cant get one of them. So Im asking you what I need to buy. Our router now is a speedport w701v. The new router should have wlan and good working LAN. It shouldnt be very expensive... give me some tips what I should look for (because Im very new with router...) and maybe give me a link where they tested many routers (and where I can trust the results).
View 3 Replies View RelatedCurrently I have 2 Lan card in My System one for communicate client pcs (Lan card Ip 192.168.1.100) and other for Internet (Lan card ip 192.168.0.100.) All client pcs are in 192.168.1.0 Subnet
Here i implement my system as router through iptables all clients are communicate through only 192.168.1.100 (clients default gateway also 192.168.1.100) Now no problem for forward rules when my system is active all clients are get internet.
Now i have problem with blocking UDP protocols i tried lot of things in net iptables -A INPUT -s 192.168.1.0/255.255.255.0 -p UDP -j DROP
But it's not blocking UDP protocols (i change UDP to ICMP Protocols then icmp is blocked every ip address)
I can successfully forward a port via:
PHP Code: ssh -L 5900:localhost:5900 test@192.168.5.1
how do I forward several ports at once. This is a wrong example but:
[Code]...
How can I tell if my USB ports are 2.0 ports?
View 1 Replies View RelatedIn my firewall I have these ports open:
21
143
110
[code]...
I forwarded ports 28900(TCP/UDP) and 5029(UDP) to my linux box for a game. Testing my ports with a website now shows these ports as "connection refused" rather than "timeout" which means the connections are getting to my system but the iptables are blocking them. But I added 28900 as a test and it still won't accept anything on this port. This is my output of iptables -L
root@BPC3:~# iptables -L
Chain INPUT (policy ACCEPT)
target prot opt source destination
ACCEPT tcp -- anywhere anywhere tcp dpt:28900
Chain FORWARD (policy ACCEPT)
target prot opt source destination
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
ACCEPT tcp -- anywhere anywhere tcp dpt:28900
What do I need to do exactly to add exceptions for 28900 TCP/UDP and 5029 UDP?
I need to ensure ports 6112 through 6119 are open. I tried using Firestarter to do this, but when I search for what ports are open, it says none of them are. I use Ubuntu 9.04.
View 1 Replies View RelatedI'm trying to set up an SSH connection from my school to my home, but not on port 22. I originally tried port 2222, but it didn't work. I called my school IT people and they said they block that port. I asked if they care if I set up an SSH and they said no, but that they wouldn't tell me which ports are blocked and which are open for "security" reasons (which I guess I can actually understand). They suggested just using port 22 or 222, but said if a ports open I can use it.
My question is, can I check ports without setting up SSH? It seems like a hassle to try a different port every day on my home SSHD file, come to school, see if it works and repeat. Is there a way I can check my computer home for connections that could connect, even if there isn't a service listening? I don't know how to do that, or even if its possible. If not, I suspect I'll just try a few until I find something that works, or just go ahead and use 22.
World of Warcraft requires that TCP Ports 1119, 1120 and 3724 are forwarded. The Blizzard Downloader requires that TCP ports 3724, 1119, 4000, 6112, 6113 and 6114 are forwarded. It can also benefit from having ports 6881 through 6999 forwarded. The World of Warcraft Voice Chat feature uses UDP Port 3724.
i use the hotspot feature to play warcraft and i am running ubuntu 10.10 ... i need to forward these ports ... any way to easily download an app to configure the phone like you would a router? its probably easy i just cant find it.
I like to set in iptables to allow access from one host to my server on any ports.Currently the iptables have been configured to deny all and to allow access only to those I've specified.
View 2 Replies View RelatedYesterday I switched from CentOS to Ubuntu, and wanted to install TeamSpeak3 which runs on ports 9987 UDP and 10011 TCP. The TeamSpeak3 worked fine on CentOS before this.
It appears to be running and netstat -an reports:
Code:
udp 0 0 0.0.0.0:9987 0.0.0.0:*
tcp 0 0 0.0.0.0:10011 0.0.0.0:* LISTEN
I believe the only firewall for Ubuntu is "UFW", am I correct? If so, "ufw status" reports:
Code:
Status: inactive
I do have other things running on UDP (Counter Strike Source servers) and people can connect just fine.
When I telnet localhost 10011 I get a response from the TeamSpeak3 server:
Code:
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
TS3
Welcome to the TeamSpeak 3 ServerQuery interface, type "help" for a list of commands and "help <command>" for information on a specific command. However, telnetting from outside just gets no answer, this is what leads me to believe it is a firewall in the way.
Since there was no response on my other post which i spent about a hour writing, ill go for something simpler. I run this on my server
Code:
# set default policy for the NAT table
iptables -t nat -P PREROUTING ACCEPT
[code]...
I have a system with one (sometimes two) ethernet ports, that works happily in an old Fedora 5 build. But I can't get it to work on a new Centos 5.4 build. Original system: One dedicated ethernet port on card always connected to the systems dedicated equipment and no external access (the system is the DHCP master for that network). An optional second USB dongle that is a second ethernet port, used for debugging and development. (This is a DHCP client with full conectivity. In /etc/sysconfig/network-scripts I have ifcfg-eth0, ifcfg-eth1 and a route-eth0. Neither of the ifcfg files needs an explicit HWADDR, which means the same ones work for all boxes. And when one needs to be connected to the network all is fine.
The system is being moved to Centos 5.4, most is working with minimal change, but I am having problems with the ethernet ports. If it only has the on board ethernet connected, all is fine. If you have the USB dongle connected things go wrong: This system brings up the USB ethernet first, and tries to assign it to eth0 (which fails), and then brings up the on board ethernet as eth1 (which also fails). I have tried forcing the behaviour of the network by setting the HWADDR(s), but this does not result in the on board coming up as eth0, it comes up as __tmpxxxx as follows:
ifconfig -a
__tmp226406138 Link encap:Ethernet HWaddr 00:80:66:07:A8:63
BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
[Code]...
Currently the only solution is to unplug the USB dongle through restart and plug in afterwards, and this wont work when the unit is remote and in the field.
As of 5 days ago I lost connectivity on HTTP, SSH, and SIP to any international address expect within South Africa.I did contact the service provider and they told me that there are not blocking any ports and everything seems fine on their side. My server is been colocated on their network.Here are our diagnostics1) I can ping from the box to any address using IP and DNS2) I can ping from an international address to the box using IP and DNS.3) I CAN NOT access HTTP, SSH, SIP from any clients outside SA.3b) CAN access all ports within SA.4)NMAP[root@localhost ~]# nmap -T5 -sV localhostInteresting ports on localhost.localdomain (127.0.0.1):
Not shown: 1671 closed ports
PORT STATE SERVICE VERSION
22/tcp open ssh OpenSSH 4.3 (protocol 2.0)
[code]....