I have a remote machine on which my server application runs. The remote server is linux based. What and all steps I would required do to IDENTIFY and SOLVE if The server is not reachable
View 2 RepliesI have a remote machine on which my server application runs. The remote server is linux based. What and all steps I would required do to IDENTIFY and SOLVE for following two problems
1. The server is not reachable
Was trying to understand the behavior of TCP when the server becomes unreachable . For this I am using vsftpd and the default linux ftp client to check the behavior.I was trying the following things. Was Trying to download a file from an FTP server using the FTP client as anonymous user. While the file is getting downloaded, I removed the network cable from the FTP server to understand the behavior of TCP when the server becomes unreachable.
As per the functionality of TCP/IP , when the server becomes unreachable for whatever reason , the client tries retransmitting the data till it can send the data or it timeouts. But in my above experiment using FTP , I can see that the FTP client is not trying to retransmit data at all . This I came to know using by sniffing FTP traffic at the client side. Is this expected or default FTP client available in Linux does not obey TCP/IP functionality properly ?
We are having two DNS servers working as master and slave in our DMZ network subnet.DMZ network consist other servers also, but only the DNS servers intermittently becomes unreachable (no ping response) from different subnets whereas the internal communication (within subnet) happens at that time.From the DNS server we are unable to ping gateway ip also when the issue arises.We tried changing the port where DNS servers connected in DMZ switch and even reformatted the OS and reconfigured DNS but nothing seems to be working.We even tried changing the IP address of the server but after few days the New IP Address also gets affected
We google around a lot tying to fix the issue but no solution has yet come up.We are not even sure whether it is server issue or a network issue.
I have two machines, one used as client and the other as server. I want to check if the port 7080 on server reachable from the client machine.How can I do that? Using telnet?
View 12 Replies View RelatedA question that I've asked myself (and google) many times but never got to an answer.Scenario:ServerA) postfix Primary MXServerB) postfix Backup MXAccording to the rfc a source mailserver can decide where to send email e.g.send an email to backup even is primary is reachable up and running.So my questions are: 1) how do I (live I mean) replicate messages arrived on any server to the other?2) How do I synchronise sent messages, message deletion, folder creation/deletion.Imapsync goes half way towards the solution but it needs to be run manually one off and you must specify source and destination.All I wanted really is a user to be able to use either server without having to worry about primary/secondary or what so ever.
View 4 Replies View RelatedI dont even know where to start looking on Google.Just in case this matters, for completeness.I've an inactive eth0 (wired ethernet link) with static IP.Other possibly relevant details:I'm using an old 802.11b card. Cant imagine this is relevant, because the internet is working fine as far as pinging anything outside the local network goes.
View 2 Replies View RelatedUntil yesterday everthing was working perfectly. Today I started my Debian Lenny and internet doesn't work. I can't ping my router successfully:
Code:
takada:/home/sam# ping 192.168.1.1
PING 192.168.1.1 (192.168.1.1) 56(84) bytes of data.
From 192.168.1.97 icmp_seq=1 Destination Host Unreachable
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i don't understand what I am doing wrong. I started a CentOS Vm through Vmware server 1.05 When I run the machine I preform Dhclient and my machine gets an IP internet works fine.
When I change my IP to static everything stops working I cant ping anything anymore I cant ping my server I cant ping my gateway I cant ping google My config is done through Webmin but I know it can also be done through /etc/sysconfig/network-scripts/ifcfg-eth0 My hosts file has this
127.0.0.1 localhost srvspam
my /etc/sysconfig/network-scripts/ifcfg-eth0 file has this
BOOTPROTO=none
NAME=""
MACADDR=""
HWADDR=00:0C:29:59:91:DE
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I hope I am not repeating a thread. I am trying something very simple: To remotely connect from a ubuntu desktop to another ubuntu server (physically not reachable). When I ping the server, it seems to be fine. However, when I try to ssh, the connection is closed by the host. I am the only one using the server. It worked fine a few hours ago and I was trying to copy a lot of data using a couple of scp sessions. At some point the connection was closed and I cannot access the server anymore.
View 2 Replies View RelatedI am working on Redhat Linux. While connecting internet through modem.Modem is configured. After activate both modem(ppp0) and eth0. When i restart my network service it is showing RTNETLINK :network isn't reachable...
View 1 Replies View Relatedneed to talk to ubuntu 10.04 via normal telnet. nstalled telnet from repository, this allows me now to contact other machines from this ubuntu, but I need also to contact this ubuntu from other machines. What do I need to do to enable telnet service reachable via standard p 23?
View 4 Replies View RelatedRunning Ubuntu 9.10. In the Remote Desktop config dialog I get: "Your desktop is only reachable over the local network. Others can access your computer using the address 127.0.0.1 or tabatha.local." I understand this means only the loopback ip address is available. All my other machines show their true local ip address (e.g., 192.168.1.104) in this dialog. Thus I cannot log on to this desktop from other machines.
When I try to do a remote logon from another Ubuntu 9.10 box (or from an XP box using a VNC viewer), I get: "Connection to 192.168.1.102 has been closed." What steps are needed to make this machine show its actual ip address? All file sharing between the various machines is working properly and all windows shares back and forth between XP and 'nix, and among the the vaious XP boxes and linux boxes are available as designed.
I installed a fresh copy of Ubuntu 11.04 on my server about 2 weeks ago, I setup remote desktop and figured to just leave the password field out as it suppose to be pre-configured to only accept local connections, well, apparently not. I was noticing some strange network activity and checked my router connections and sure enough I see port 5900 to the server, open vino icon and see that there is someone else connected! (IP of unauthorized user: 77.29.51.239 ).. Immediately kick them and set a password. This should really be addressed and/or a password should be defaulted or at the very least the "Your desktop is only reachable over the local network." should be removed.
View 9 Replies View RelatedI've two internet based server ( xx.xx.xx.xx and yy.yy.yy.yy ) The Y server is running VNC server and is responsible for answering to VNC sessions. But I need to hide the IP of Y server so I want X server to be as VNC Proxy and redirect all VNC sessions to Y server.
I guess the best way is to use iptables but actually I can't get it working so
I've got a machine running Ubuntu Server that is on several VLANs. Each VLAN has its own subnet and the server has an address on each subnet. The switches are set to allow tagged traffic to the server for each VLAN that it is on. Switch ports ending with workstations are given untagged ports on whatever VLAN is appropriate. Workstations are given addresses on a subnet for each VLAN via DHCP. All this works great and hosts on any subnet/VLAN can access the server as normal via its address on that subnet/VLAN.
Accessing the machine by its address on a non-local subnet is where I run into a problem. Inter-subnet traffic has to go through a router, which has been set up appropriately. Running tcpdump on the server and pinging it from a workstation on a subnet, using its address on a different subnet, shows the server receives the ping, but sends no response:
Code:
sudo tcpdump -i vlan4 -n
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
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In my httpd log I always get this recurring error
[notice] Digest: generating secret for digest authentication ...
[notice] Digest: done
[warn] RSA server certificate CommonName (CN) `srvspam' does NOT match server name!?
My Pug Server has worked faithfully for many years just sitting in a closet. It is designed wo that you never need to add a monitor or keyboard as it is administered through a web interface. Recently it had a problem with the motherboard and I had to replace it, but the machine is now working. However, it no longer is visible as a network drive on my Windows machine.Unfortunately I have no idea where to start looking to see what the problem is. I did attach a keyboard and monitor and logged on, but everything looks okay (I can see my files, etc.).
This is an old machine (c. 2003), so has an old version of Linux (I have no idea what version, or even how to find out). Since it is never meant to be used directly it doesn't have any GUI installed, so I have to do everything using command line.Does anyone have any suggestions as to how I can even start to determine what the problem is or how I can go about trying to fix it? At this point I would be happy just to get the files out and replace it with a newer NAS.
Just something that struck me while working on our virtual servers today.
I have bonded 3 NICs at the host in Ubuntu Server 8.04 LTS. They are using mode 0 for Round-robin. Point is to increase the speed/performance of all the servers, but mainly the fileserver. The fileserver is a virtual server running Ubuntu Server 8.04 LTS on VMware Server 2.0.
1) I noticed the NIC in the slave OS reported link speed as 1000 and Im unable to change it as the NIC (virtual one) doesnt support it. Does this not really matter, as the NIC doesnt exist, and it will run at higher speeds anyway? Or do I have to remove the bond on the host, bridge all 3 interfaces from the host to the slave OS, and then make a bond in the slave OS?
2) While at it, does mode 0 only increase performance on data being sent from the host or does it also increase the available incoming bandwidth?
On a remote system, when all you have is the ssh CLI -
How do you find out the ip addresses for:the Gateway
the DHCP server
the DNS server
Don't need to make any changes.
Which commands will display this info?
In Gnome Places->Connect To Server dialog, I am having problem using the Custom Location Service Type. I enter in the URI as
Code:
smb://username:password@ipaddress/share_name
I get an pop up error message that says:
Quote:
Cannot Connect To Server. You must enter a name for the server.
Which would be fine if there was actually a place for me to enter the name which there is not. What am I doing wrong. This is the first time I have tried using the Connect To Server dialog. Normally I just use a script I wrote to mount my share in a folder on my local drive as some programs cannot access the mounted network folder. In a browser all I have to do is:
Code:
smb://ipaddress/share_name
I tried using Windows Shares, but that did not work either. It does work if I click on network and access the share that way, but some programs like firefox and a few others that I want to save a file to my network drive do not show the network unless the share is mounted in a folder. So, I wrote a script:
Code:
#!/bin/sh
#mount ext storage drive
mount -t cifs //192.168.0.2/files -o username="username",password="password" /mnt/files
This works and I can use this, but it would be handy if I could just use the Connect To Server dialog.
we have deployed linux Santos 5.4 server and window 2003 server. we are able to ping window server from linux but not linux server from window. all are in same network.
View 1 Replies View RelatedI set up a ubuntu server 10.04 lts as file server in a network filled with xp, win 2003 and win 2008.
I noticed that if from any bill's SO machine i copy a file (for example a vob file of 1gb, or a lot of doc and pdf files) in the samba server, while the copy is in progress if in another windows I browse other folders shared in Samba, the copy process stops and say ' the name in the network is no more available( or something like this). It seems that samba pay attention on the fact that a user is browsing the share and doing so it seems that Samba forget that in one of its share there was a copy in progress, very annoing. A file server cannot do that, in this way is useless.
I would like to setup 2 linux machine each with two ethernet cards, and need to connect to two subnet e.g. 192.168.*.* and 10.0.*.* . If one linux machine out of order, the other will take over all the services(1 httpd and two named(192.168.*.1 and 10.0.0.1 as server ip). What network config is best and easy to failover to other machine?
View 1 Replies View RelatedI have 2 ethernet cards but when I look at the Network configuration in "Hardware Tab" I have another acx wireless network. How to delete that because In my system Idon't have wireless card..probably installed before but want delete it now.
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then windows can ping server and resolve ip address and browsing Internet but can't ping [URL]... result is Request time out. ICMP already enabled in iptables.
I have multiple public ip addresses.My DSL modem blocks ping from a server behind the modem (nb6+4w) modem lan ip (gateway) is xxx.xxx.xxx.105the server is xxx.xxx.xxx.107If I DMZ this server it responds to pings.If i don't want to use DMZ, what service is ping using.I have set up virtual server 443 to this 107 ip as it's a SSL server
View 5 Replies View Relatedi know exactly what i need to do, im just not familiar enough with command line to do it properly.i have 7 computers.the first 4 are connected to a router via wireless at one end of the house. of the last 3 only 1 will be able to access the router via wireless, so it needs to share it's one wireless connection via ethernet. this computer i'm going to call 'server'server will have two IP'swlan0 192.168.1.6 this connects to the router that has internet access.eth0 i intend to have the following settingsip:192.168.0.1sub: 255.255.0eth0 will connect to a second router, where the cat5 cable goes from the server, into the internet port of the router where i will define the router's static IP:IP: 192.168.0.100sub: 255.255.255.0gateway 192.168.0.1i have then set the router IP for LAN handling as 192.168.27.1 and all ethernet connections will have a 192.168.27.x IP.
so i need to know how to, without a gui application, use the terminal to assign server eth0 a proper IP address, and tell the server to take the connection it has and share it through eth0 to supply internet for the last 2 computers via ethernet.i had it set up in this way with a windows machine being the one that had the wifi access, but i'd rather have it setup for the ubuntu server to do this task. security is imperative for these 3 remaining machines, so just getting 2 more wifi adapters for a connection to the initial router isn't an option.the 2 that connect to server do so through SSH and though server IS connected via wireless it only makes outward connections through
Im trying to make an ubuntu server box my entrypoint to my networking. Meaning itll function as a server, a firewall, and a gateway. so i already installed dhcp3 and a dns server.
I have 2 ethernet cards in it. So now i wonder, should i the second card into a router's modem/wan port and make the router a switch? or should i plug it into one of the routers lan ports?
I am trying to get a Linux (Slackware 13.37) working in a Windows networking environment. The IT support for this organisation does not extend to Linux support, so I'm limited in what help I can get for this.
I'm trying to get to the point where I can get to the internet to download what I need on this Linux machine.
The situation is this (*fictitious addresses used) -My Linux machine uses a fixed IP address (10.100.150.21)
My Windows machine uses a DHCP assigned IP address (10.100.150.213)Both Linux and Windows machine are configured to access the gateway server (10.100.150.1)So, I can ping the Linux machine from the Windows machine and vice-versa.I can ping the gateway machine from the Windows machine.I can browse Windows Shares on the network via SMB from the Linux machine.I CANNOT ping the gateway machine from the Linux machine with the Destination Host Unreachable message being the error message.
For actual internet access I need to access a proxy server but since the Linux machine can't even ping the gateway server, it fails to ping the proxy.Now, I have been told the gateway is a HW based router and for Windows machine they use some software for authentication to connect to the network. This software isn't available for Linux, so that's why I've been told to use a fixed IP address.My experience of networking is pretty basic and most of the Linux setup is done via running Slackware's setup program.
I want to use my server software for more than just a web server. Any good links on setting up a Domain and roaming profiles?
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