When I am running linux on my laptop, my ssh session to a particular server keeps getting randomly dropped. What should I do to troubleshoot the problem?
View 4 RepliesI've recently installed Fedora 14 (x86_64) on my Alienware m15x laptop which has a NVIDIA GTX 260m onboard. Now I have followed leigh123linux's guide to installing those drivers on F14. The installation is a success and everything seems to be in working order, until the system randomly logs the user out and/or restarts the session with no warning. The screen goes black and the nvidia logo appears and then its back to the login screen again. This can happen many times with no apparent stop insight. This does not happen with the default F14 drivers that come with the installation, I have tried several re installations of the Fedora OS and several re installations of the NVIDIA driver, i still have the same problems.
View 3 Replies View RelatedIn my Fedora13 machine, while in mobile broadband, i can ping and skype outside, but cannot browse/yum etc. Few output that may be of relevence are here:
$ netstat -s
IP:
149468 total packets received
6 with invalid headers
16174 with invalid addresses
0 forwarded
0 incoming packets discarded
118821 incoming packets delivered
101331 requests sent out
124 outgoing packets dropped
866 dropped because of missing route .....
My X session is randomly crashing with the following backtrace:
Backtrace:
[ 36277.010] 0: /usr/bin/Xorg (xorg_backtrace+0x28) [0x483068]
[ 36277.010] 1: /usr/bin/Xorg (0x400000+0x5e6d9) [0x45e6d9]
[code]...
Whenever I try to login via SquirrelMail into my account I get this error message:
ERROR: Connection dropped by IMAP server.
I have Dovecot installed that constantly "commits suicide" due toe constant time changes on my server.But I don't have any NTPD or anything running.. If I do a Code: watch date it updates the screen every 2 seconds, and you can clearly see the time flip back a few seconds, and then go back to the correct time.. Sometimes it goes back a few minutes, and back to normal..
I literally did this 10 seconds ago..
Code: [root ~]# date
Tue Feb 15 17:15:11 GMT 2011
[code]...
I have an Ubuntu 11.04 Server set up for my small office whose sole job is to run as a samba file server. The problem is that it randomly hangs. For example, I can connect the clients just fine, however if left idle it tends to take a few moments to work when you try to go back into the shared folder or drive. The client will behave like it is disconnected and is trying to search for the drive only to a few moments later, go right back to normal behavior.
If I ping this server while this is happening my requests will time out for a little while and then just start working. The same thing happens when I try to connect with Putty or through WebMin. One second its unreachable then the next its fine.I have already tried swapping out patch cables (which actually seemed to work for about 2 weeks) and I have patched it to an alternate port on the switch. The only thing I have not done at this time is to change the NIC.All the clients are running Win7 with the exception of two XP machines.Simply put, its like the machine just goes dormant for a while until you ping at it for a while to wake it back up.
So what I need to do is change my MAC (HWaddr). I'm using rc.local with code:
ifconfig eth0 down
ifconfig eth0 hw ether 00:04:76:18:2F:4F
ifconfig eth0 up
[code]....
I am running SquirrelMail version 1.4.8-5.el5.centos.10 on a CentOS 5.6 64-bit distribution with MailScanner 4.83.4, Sendmail 8.13.8/8.13.8, and Dovecot 1.0.7 release. One user is having problems connecting via the SquirrelMail interface to his e-mail. Whenever he tries to connect, he gets the following error message:
Quote:
Error: Connection dropped by IMAP server with dovecot
I have tested another user account, and that user is able to connect without issue. I confirmed the presence of dovecot.index, dovecot.index.cache, and dovecot.index.log files in the user's <HOME DIR>/mail/.imap/INBOX folder. The /var/log/maillog files do not list any apparent error messages with SquirrelMail.
I have UBUNTU server 10.04 LTS with 3 NIC "eth0" local and eth1,2 as internet connection and it acts as firewall, http proxy and samba file server ,I installed Zentyal panel manager for my server for easier management I did not configure any specific rule for my firewall but I have some problem with my clients who wants to connect to my server as gateway or as file server even my self experienced these problems too. these problems are as follow:
1. some time for a few minutes (maximum 10 minutes) my server block some of my clients to access it or internet but just for minutes but it is very annoying.
2. all of my clients those who login to an https servers or login to their mail or those who has some software like team viewer say that they are logging out from their session randomly I mean some of them logging out from their mail(yahoomail or googlemail ) or disconnecting from teamviewer connection or as I saw team viewer disconnecting for a few seconds and then comes back again. but I did not set any thing in my firewall or other services. this is my complete iptable rules:
My wireless connection keeps getting dropped very frequently. I am on a Dell XPS m1530 and I will just be on the interent and it just disconnects from wireless and I have to connect back. It is super annoying. I am on the latest version of ubuntu.
View 4 Replies View Relatedmy laptop running 10.10 and a dell. the college is witch i attend's unsecured wireless network keep disconnecting me from every on average 45 minutes to an hour ands will not re connect for about 10-15 minutes. it works fine anywhere else i go but here i get dropped.
View 1 Replies View RelatedOne of our RHEL 5.3 servers has trouble about 30% of the time with TCP-based communications, but it does not seem to be firewall issues. From another computer on the same switch, you can SSH to the server sometimes and other times the SSH command will just hang. When it hangs, you can often just Ctrl+C and try it again and it works. Same with HTTP connections. You'll get part of a web page and then FireFox will just hang waiting for the rest and eventually time out. Same goes for communication initiated FROM the server. SSH'ing from the server to any outside server or connecting to any web site works sometimes, but most times not. iptables if off. No other firewalls are running. Tcpdump shows communication gets so far and then stops. It does not matter whether tou run tcpdump on that server or the client connecting to it. Either way you see the connection stops working. MEANWHILE, pinging with small or large packets works flawlessly. 10,000 packets, zero drops.
View 5 Replies View RelatedI've recently installed Ubunter 9.10 Server Edition to use as a NAT firewall for the lab I run. I'm using iptables to do NAT forwarding and everything works great except that, occasionally, connections seem to break. Ssh connections close with "Connection reset by peer" and HTTP connections just stall out.I believe this has to do with the firewall's internal network interface occasionally dropping packets.
View 2 Replies View RelatedI have question regarding netstat? When performing a "netstat -s" I receive the following information regarding dropped packets under IP:
IP:
93978695 total packets received
0 forwarded
0 incoming packets discarded
79472157 incoming packets delivered
65235033 requests sent out
29527 outgoing packets dropped
However if I run a "netstat -i" I have no dropped packets whatsoever: (apologies for the table format):
Kernel Interface table
Iface MTU Met RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flg
bond0 1500 0 34326528 0 0 0 72755307 0 0 0 BMmRU
bond0:1 1500 0 - no statistics available - BMmRU
bond1 1500 0 28605491 0 0 0 20948952 0 0 0 BMmRU
eth0 1500 0 34199550 0 0 0 72755278 0 0 0 BMsRU
eth1 1500 0 126978 0 0 0 29 0 0 0 BMsRU
eth2 1500 0 97911 0 0 0 1 0 0 0 BMsRU
eth3 1500 0 28507580 0 0 0 20948951 0 0 0 BMsRU
lo 16436 0 34094225 0 0 0 34094225 0 0 0 LRU
I have configured postfix and sendmail in my fedora11 i phased some problem i added before installing 2 users they can able to logged in squirrel mail but when i create a user they cann't able logging into squirrel mail they are getting bleow error
##########################
ERROR:
ERROR: Connection dropped by IMAP server.
###########################
I am using ubuntu 9.10. Configuring my firewall using guarddog. I have setup a rule to allow traffic OUT on port 7078 UDP, and just because i'm having problems i added an IN rule.
# Create the filter chains
# Create chain to filter traffic going from 'Internet' to 'Local'
ipchains -N f0to1
[code]....
I've been using my current laptop since Ubuntu Edgy Eft and, since then, I never had any problem with wireless ( Network controller: Intel Corporation PRO/Wireless 3945ABG [Golan] Network Connection (rev 02) ) Since I upgraded to Lucid, my connection is dropped approximately every 3-4 minutes for 10s. Network-manager doesn't show anything but it is well visible with the netspeed applet that shows a warning sign "No connection" instead of the speed.This is very annoying and frustrating. I recall having seen the same issue in an blog article where the author was talking about his upgrade to lucid. It was just one line and I didn't care a lot at the time and cannot find the article back.
Is there anyone having heard about a possible issue ? (I've upgraded from Karmic when Lucid was still in Beta, so it might be the cause).
I'm working right now with ubuntu 11.04 on my asus ul30vt-x1, my wireless n network is working on a linksys e3000 router, my issue is basically with long file transfers. When the issue started i was reaching speeds of 100 Mbps through my wireless network even when I'm connected at 150 Mbps. However when at this speed, I don't know why, the connection is dropped after some minutes or even seconds. I made some testing on windows, I'm reaching 70 Mbps there and no problem at all with dropping the connection.
So my conclusion is that for some reason the linux driver, in my case, is not able to handle such speed of 100 Mbps. I know that a wireless network will have a throughput of aprox 60% the wireless speed. Right now im trying to apply traffic shapping to my transfers so i can get 70 to 80 Mbps, its being working so far.
I've forwarded incoming connections on port 25 to my virtual machine with the following commands:
sudo iptables -t nat -A PREROUTING -p tcp -i eth0 -d 10.1.1.3 --dport 25 -j DNAT --to 192.168.56.101:25
sudo iptables -A FORWARD -p tcp -i eth0 -d 192.168.56.101 --dport 25 -j ACCEPT
The strange thing is the connections coming through in the virtual machine seem to be getting dropped. A port scan from the internet says the port is closed, but it is not the case as I can see the connection coming through. As you've probably worked out, I am running a mail server. When I send myself test mail, the connections from the senders mail server also gets dropped.
I've run into a of a routing issue pertaining to packets leaving a firewall, traversing and IPSec tunnel, hitting the target and then returning via a different tunnel, finally arriving back on the source firewall but on a different interface from where it started. Once the packet has returned to the firewall it is dropped I've been unable to discover the reason for the drop. Two sides to the system, Firewall A and Firewall B. Each firewall provides the default gateway to its respective side and offers a backup IPSec tunnel to the high capacity tunnel handled internally. The Layer 3 Switch uses OSPF and takes care of the bulk of the behind the scenes routing between the sides. In case of failure the Layer 3 switches direct traffic to use the Firewall tunnels to route traffic.
View 2 Replies View RelatedI'm running a Debian Squeeze 6.0.1a box that's connected to my ISP via an L2TP connection that's managed by OpenL2TPD. The box is configured to perform NAT from local clients (on eth0) to the internet (on ppp0).
However, I'm having an issue with TCP packets that are sent from the box itself to the internet (packets originally coming from the local clients get sent and received over the internet just fine)
I'm using this Python app to test this:
Code:
#!/usr/bin/env python
import socket, time
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind(('', 5003))
s.listen(1)
while 1:
conn, addr = s.accept()
[Code]...
I am trying to connect to a windows 2000 VPN server at work, with my current settings in DOES connect to the VPN and i can ping the domain server which is 10.1.1.2 but the first issue is i cannot ping the other computers on the network(via hostnames) can't remember the ip address of the other machines . second issue is when the connection is established and i RDP into 10.1.1.2 ok great i am connected to the server but any interaction in the RDP session even moving the mouse on the screen kills the session and the VPN connection fails.
Running Ubuntu 10.04 LTS 64Bit
Image of current settings in network manager:
Syslog:
Code:
May 11 12:08:04 oliver-desktop NetworkManager: <info> Starting VPN service 'org.freedesktop.NetworkManager.pptp'...
May 11 12:08:04 oliver-desktop NetworkManager: <info> VPN service 'org.freedesktop.NetworkManager.pptp' started
[Code].....
To install XRDP server do
[code]...
To connect server use mstsc.exe in windows, rdesktop in linux - if you do not have it yum install rdesktop. But if you use different from english localasation of fedora, you will see only english Gnome and instead of your local fonts in terminal
[code]...
Now you can use fedora RDP session with your native language.
I'm running ubuntu 11.04, and using firestarter for my firewall. Logging events, all good, but I'd like to be able to (tcp)dump the packets being dropped/rejected. Wireshark is great after the event, but can I hook iptables and tcpdump together somehow so the system logs the entire packet rather than the summary when it says "no"? I've had a quick look/google, but can't find anything. I'm sure somebody must have wanted to do this before - any pointers people?
PS - will keep looking and post the answer if I find one....
with my other ethernet card problem solved, I suddenly run into this:
Code:
eth1
Link encap:Ethernet HWaddr 00:02:e3:16:37:4c
inet addr:10.0.2.1 Bcast:10.0.2.255 Mask:255.255.255.0
inet6 addr: fe80::202:e3ff:fe16:374c/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
[Code]...
This card was working perfectly fine up until....an hour ago and it started doing this. My iptables isn't blocking it somehow, because I didn't change anything. I tried reverting to an older kernel and that didn't help. It's not the network cable, it works fine in any other card. Also, the dropped packets seem to count down? It seems to go down by exactly one every time I run ifconfig, no matter the length of time in between running it.
when I change the hostname on my Ubuntu server, the DHCP clients table in my router is dropped.I'm running 32-bit Ubuntu Server 10.10. My router is a Linksys WRT54GL with firmware version 4.30.15. I'm changing the hostname by modifying /etc/hosts and /etc/hostname. I've also tried changing the hostname using the Linux hostname command in a terminal, but this does not seem to behave correctly according to the manpages (it does not actually change the hostname, or update either of the aforementioned files).
I've also tried using a different router - a Linksys BEFSR41 - but the DHCP table is still dropped when I change the hostname on my server (although this router is not all that different from my other one).
My wireless is flakey -- dropped connections, poor speed, etc. As diagnosis, I loaded the 'wavemon' utility so that I might watch the radio and signal and noise.Things will be good, then fall off, then get better, then go away entirely. Repeat continuously and randomly. For these experiments, my laptops -- more than one -- are on a table.The table is roughly 15-20 ft laterally from the access point. The access point is also 8 ft above the floor vs. 3 ft table height.(grin) While the signal "wobbles" everything else is mechanically stable and otherwise not moving.
View 11 Replies View RelatedI'm having a bizarre problem where my network connection stops working randomly. At first I thought it was a DNS issue since Firefox simply chilled out on "Looking up [hostname]" until it timed out, but after further investigation (pinging IP's, "host" and "dig" being unable to reach servers) it became apparent that I couldn't even access the DNS servers i.e. the Wicked Connection of the East was most sincerely dead.
There are two strange things about this: one, there are no errors except "timeout". The network manager is happy, Firefox is happy until the lookup fails... Two, the failures only start *after* DHCP configuration. DHCP configuration never has any trouble sending or receiving packets. I'm going to try static IP and whatnot to see if that helps, more information later.
I have a Netgear DG834 ADSL router (v3) which I have used for a couple of years. Prior to that I had a v2 of the same router, but upgraded for the one that supports ADSL 2+ (here in the UK).
Recently I have been having problems with the connection often being dropped, and when I access 192.168.0.1 for the router admin page, when it is not working I get no IP address listed for that of the ISP's server, and sometimes as well the upstream and downstream speeds are listed as 0 kbps.
Usually this was resolved by rebooting the router.
However, for the last couple of days, when using Ubuntu 9.04, the page of the router at 192.168.0.1 will not load. I have tried numerous different browsers, and none of them will give the router admin page.
When I tried booting from a live CD of Fedora 13, the router admin page came up just fine, no problems (although still not getting a proper connection to the Internet).
I was going to try to use the older router I had, but so far, as I cannot access the router admin page in Ubuntu, I have not done so (not had the time, and now I am at work posting this).
So there must be a problem in Ubuntu that is preventing it showing the router's admin page. The Network connection details show that the router has given the PC an IP address of 192.168.0.6 and the DNS servers are listed, so I know that Ubuntu is talking to the router, but it is not allowing me to access its settings in any way.