CentOS 5 Networking :: Lost The Ability To Ping/ssh/http Remote Server?
Dec 21, 2010
Some time yesterday, I lost the ability to ssh my remote server, or even visit any webpages it hosts.
I've explored hosts.deny, /var/log/secure and even turned iptables off to see if it would fix anything. To no avail. Here's what my ssh login attempt looks like:
I should have poked around a little harder but I remember that I was experimenting with an ssh proxy when a the hotel. Apparently when I setup the proxy settings in Chrome I must have clicked the "set system wide" button and set every browser to browse through the proxy. I even had to enter a password to change that setting. I thought I changed it back after experimenting but apparently I did not. Today I just started my Ubuntu 9.04 laptop to find that I can not browse web pages. I tried multiple browsers including Chrome, Firefox and Epiphany. Each one gives me the same error message:
Epiphany: "www.google.com" dropped the connection. The server dropped the connection before any data could be read. The server may be busy or you may have a network connection problem. Try again later.
Firefox: Connection Interrupted. The connection to the server was reset while the page was loading. The network link was interrupted while negotiating a connection. Please try again.
Chrome: This webpage is not available. The webpage at [URL] might be temporarily down or it may have moved permanently to a new web address.
So now most of you are ready to ask me to check my connection using ifconfig etc. But here is the rub: I can download updates, install software using apt-get, ssh, scp, download files with wget, ping web sites and browse the net using the text browser Links (so pretty much everything else works.) I cant figure out what has happened. The last time I used my laptop was this past weekend in a hotel using their wireless and then connecting using a captive portal. And everything worked fine.
My only theory is the hotels captive portal might have messed up something but what that is is beyond me. I tried using both wired and wireless connections and still the same thing. Re booting does nothing. So in order to surf the web I have to use my virtual box Windows XP image. So here I am typing this message in Firefox on windows XP in a virtual machine on my Ubuntu laptop that for some reason will not let me view websites.
My problem is the following:I can only connect to the internet and download through the FTP, but not through HTTP.I am in a hospital at this moment and have a netbook (Lemote Yeelong). Also there is a computer here with internet access.I would like to access the internet by using the cable from the computer.I configured my netbook just like the local computer (same host name, same MAC address, DHCP), just to be sure.I can ping google.com and I also can download from ftp.debian.org though ftp.However, when I try to connect to google.com through epiphany, it just loads and loads without success
I'm trying to set up a server for an NPO who connects to the Internet through an internal proxy (Websense). I can't access the Internet unless through the proxy.
Since it's a server I did not install a GUI so I'm wondering how to connect the new server to said proxy server. I have the IP address, port number and username-password for the proxy server. The new server has a static IP address and is ready too go!
I have configured (bind) my server with multiple static IP. I can ping the main IP from outside but not the other IP . I can ping all the IP from localhost but not from the internet. I do not have any external firewall or blocking device. server is directly connected via modem. If anyone could advice me for why i cannot ping other Ip's
i am forwarding HTTP request to a internal server, it is quiet successful but access logs donot show the ip of the external m/c. Rather it shows the ip of the machine on which i have enabled port forwarding.
I have installed Centos 5 on a virtual machine (esx4i). I set it to obtain an IP address from the DHCP sever, which is a broadband router, it has been given an IP address of 10.10.11.159 the router is 10.10.11.1 but I can't ping the router and I can't get any access to the network! I have a SCO Openserver server on the same physical box and it works fine so I know the network card & cable is ok.
Is there any tools in linux same as "http-ping. This tool shows for any request : 1-The HTTP return code (and its brief textual description) 2-The number of bytes returned by the server (excluding headers) 3-The time taken to complete the request (i.e. round-trip time)
I posted it on another forum, but could not get response,So I have this cenOS, Ubuntu and windows operating system running on virtual machines.Now I gave them manual ip address, both ubuntu and windows machines can ping the default gateway, but not the CentOS.It should forward 0.0.0.0. to my cisco router address(192.168.5.254),
I have OpenVPN running successfully on a CentOS Linux server. All remote clients connect without a problem and can ping the server LAN (10.5.0.0/24) . The server address is 10.5.0.1. All network shares on the server are available to the remote clients via SAMBA shares and this works well.The problem is that I am unable to get the remote clients to access services on the LAN clients. For example, there is a webserver running on a Windows XP PC (on the server LAN @ 10.5.0.2) with no firewall enabled. The remote VPN clients can ping this webserver at 10.5.0.2, but cannot browse the webserver at [URL]. All clients on the server LAN can however browse the webserver. The remote clients are using Windows XP and VISTA with OpenVPN 2.1.1.
I am new to VPNs and networking, but from my research, it seems as if this may be a routing issue. I would appreciate any help you may give in getting the remote clients to access the services on the LAN clients (other than the server @ 10.5.0.1).
I'm trying to setup a Centos 5.6 Squid Proxy Server with Content Filtering & Antivirus Scanning Incoming HTTP Traffic from the Internet
I then proceeded to setup an configure the Proxy Server, i was able to test and confirm that Squid and Dansguardian Content Filter is working, however i dont know if Clamav is scanning HTTP traffic before it hits the client/server. Is there a way i can check if the Antivirus scanning is working.. is there some log file or real world test i can i can do to confirm that Clamav is scanning incoming traffic or even blocking potential viruses ??
Anyone who has squid proxy server with Clamav configured and its working can share there settings/setup with me and how they tested it ??
i have a problem........ How to redirect local http port to remote ip ddress(192.168.10.64) using iptables..my destro is Centos 5.3 my rule is this iptables -t nat -A PREROUTING -s 0/0 -d <my local ip> -p tcp --dport 80 -j DNAT --to-destination 192.168.10.64
So, I have an Virtual Machine running CentOS 5.4. It sits behind a hardware firewall which also does NAT'ing. I've set up plenty of these, so I know for sure the firewall and NAT rules are set up correctly. From the host, I can ping anything in my subnet and the gateway. But I can't ping anything else beyond the gateway. I can perform DNS queries and when I try to ping, it finds the appropriate IP address.But from the outside, I can ping the PUBLIC address (It's a 1 public to 1 private address NAT, not 1 public to multiple private). I've tried it with IPTABLES on and off, with no change.
I've been running Jaunty on my drive D: with XP Professional on a separate partition. Today I formatted a different drive, C:, which had previously shown up in GRUB as XP Home Edition, and placed a new XP Professional on it.
Now when both HDs are connected, C: boots without GRUB starting, and when I disconnect C:, the GRUB on D: starts, but cannot find the XP Professional NTDLR. I don't want to take up too much of anyone's time here with this; I'm mostly just curious as to what may have happened?
I've been using 10.10 for almost a year with no problems. Then last week I plugged in my MP3 player (ONDA vx777le) and it did not automount as it usually does. I have since found that any USB stick will not mount any more either. They show up in lsusb
Code: ken@ken-desktop:~$ lsusb Bus 005 Device 002: ID 046d:c517 Logitech, Inc. LX710 Cordless Desktop Laser Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub .....
I also see this in messages when I plug it in: Code: Apr 17 01:40:21 ken-desktop kernel: [24379.152035] usb 1-4: new high speed USB device using ehci_hcd and address 14 I'm assuming This happened with some update but I don't know what one.
I need to redirect all http/https/ftp traffic through the remote proxy, but when I changes connection settings in browser or in System->Preferences->Network Proxy it doesn't work well: instead of getting page content browser asks for saving some short (8 bytes) file with the same content for all requested pages. It happens in Chrome/Opera/Firefox. This proxy requires authorization and works on computer with Windos XP. It worked well when I was using Windows 7 and Proxifier, now I have Ubuntu 9.10 with all available updates.
I wanted to update to the latest ubuntu but was short a couple of gigs in my linux partition. So i created a Gparted Live bootdisk and repartitioned my hard drive: i took 5 gigs from my mac os partition and moved it to the linux partition...
After that i could no longer see any boot option aside from Mac OS when starting the computer with the option key held down. So i thought maybe rEFIt might be the solution (i have no idea what i'm doing really) and installed refit. I'm not sure what that achieved - i can still only see one boot option (mac os - although it's now named 'refit'...)
I am semi new to linux and i was getting the hang of it until just recently. I'm trying to do some web design using php and mysql. In my reference material (the all in one desktop reference {for dummies}). At some point I needed to do something in /var/www but I ran into a permissions problem so I typed: Code: chgrp -v -r guy0203 /var/www 405 chgrp -v -R guy0203 /var/www 406 chown -v -R guy0203 /var/www
Afterwards in some subsequent step it suggested putting the files in /usr/src/mysql. Since I didn't have that folder I used mkdir and created it. Then I tried adding the files I needed to that folder and got denied on the grounds of not having permissions once again. So tried something like this: Code: 451 chmod 777 /usr/ 452 sudochmod 777 /usr/ 453 sudo chmod 777 /usr/
It was a 755 originally but I couldn't copy those commands. It turns out as that I had two terminals open in different desktops. one of them was a root terminal. It was at this point that realized that I was in that root terminal and decided I was done 'learning' for the day. I decided to listen to some music (which is located in my windows partion) and ran into a problem. The prompt that pops up to normally asks me for my admin PW to mount the drive. Now just vibrates like an incorrect entry was received, says authentication error and says I am not authorized to mount that drive then I went back to terminal to fix it, and when I tried to elevate myself to SU:
I got this: Code: guy0203@guy0203-laptop:~$ sudo su sudo: must be setuid root guy0203@guy0203-laptop:~$
I don't know what to do now but I think I totally killed this OS. If so is there anyway to save things if I have to reinstall?
1)I lost ability to move application window. eg, The firefox window is stuck and anchored at the upper left corner. I can still resize by dragging the lower right corner. I notice the upper right corner resize tab disappears. If open another application, it is again anchored at upper left corner and cannot be moved.
2)under Settings>Xfce Setting Manager> Window Manager, all the icons are gone. Same inside Window ManagerTweaks. I used "xfce4-panel" in terminal, it doesn't help.
Before today when I turned the machine on there was a black screen with many Linux kernels to choose from and Windows.
I created another for Fedora and installed it on there - the Ubuntu root partition is still there.
When I boot now, there is a blue Fedora screen with just it and Windows.
To make matters worse Fedora doesn't work with my graphics card (Matrox). I would like to get Fedora working but still want to have the ability to use Ubuntu again.
What do I need to change to be able to boot into Ubuntu again and how do I do it?
Just upgraded to 9.10 and lost the ability to use my scanner with VueScan. No help at their site or the Avasys Corp. site, where downloads of the "driver" refuse to load due to various conflicts. Has anyone gotten VueScan to work with 9.10 and how on earth did you do it? (Scanner is an Epson Perfection V500 Photo.)
I have recently downloaded Ubuntu 10.10 and installed it onto my laptop, alongside with pre-installed Windows XP. I'm very happy with Ubuntu and find it a lot better than many other operating systems. However, I have stumbled across a problem recently: I don't seem to be able to suspend ("sleep") the laptop and neither can I hibernate it. These options worked so far and if I remember correctly, this started when I updated my kernel to 2.6.38. Since then, I've lost the options to sleep and hibernate, and when I close my laptop lid, I get a message "Unable to suspend".
Also, a side question - why does video run so slowly on Ubuntu using VLC? This happens to me when watching .mkv videos. Many frames get skipped and there are visible artifacts, in fact, so much that the video can barely be watched. Actual FPS drops below 1, so one frame stays on screen several seconds. I tried tweaking the options, choosing different demuxers, codecs and graphics output. This happens only while running on batteries and works fine under Windows, I have no idea why. Under Windows the video is played using Media Player Classic and ffdshow, if it makes any difference.
I have a very large graphics library that I use regularly, but all files are in WMF format. Prior to upgrading to Ubuntu 11.04 (was previously on 10.04), these files would preview in Nautilus, and GIMP would automatically convert them when they were opened.
Now, these files no longer preview in Nautilus, nor do they open and convert in GIMP. Package libwmf0.2-7 is installed.
I'm relatively new to Linux. My netbook ran updates yesterday for Ubuntu and now I am unable to reconnect to wireless network connection. I am using WPA2 encrypted security. I am able to connect via wired LAN. Also, when I went to connect using USB mobile connection, I get an error "unable to mount location". I get the same error if I try to connect my external CD drive. I am using Ubuntu 8.04 with Gnome desktop (2.22.3) on a Dell Mini 9.My wireless device is using Broadcom STA Wireless driver for an 802.11 wireless card.
I installed Mepis to a separate partion (shares swap) and now the option to use, originally installed, Ubuntu does not appear at start up. Is there a way get this option back?
I'm relatively new to Linux.My netbook ran updates yesterday for Ubuntu and now I am unable to reconnect to wireless network connection.I am using WPA2 encrypted security.I am able to connect via wired LAN. Also, when I went to connect using USB mobile connection, I get an error "unable to mount location". I get the same error if I try to connect my external CD drive. I have tried to force mount but no luck.
I am using an virtual machine. where I need to ping from one machine to another. earlier I was able to ping. But after going to google.com once, I cannot ping back to this machine.
But if I gave ping -I eth1 <IP> then I can ping.
I cannot install any package, so tell me solution which includes not installing any package.
I have been trying (unsuccessfully) to remote access my girlfriend's Ubuntu machine to fix a few things. The problem is that she lives in Japan and I live in RI, USA! Is it even possible to ssh or Remote Desktop her computer with such a high ping rate? (average ping time is 300ms) If so why can I not connect?
I have Linux server with VMware Server 1.0.8. When I creating a virtual machine, I can not "send" a PING to the virtual machine. In the virtual machine, I have installed CentOS 5.3 (32bit). In the virtual machine I have defined the addresses IP. So, whey I can't "sent" a ping to the virtual machie? I have to set something on the Linux server?