I have two CentOS servers on the same LAN. One is CentOS 4.7 the other 5.2 They both also have a WAN interface to the same remote network. On CentOS 4.7 I can ping the remote network through the CentOS 5.2 server. i.e. ping -I eth0 remotehost On CentOS 5.2 I can NOT force the ping to go out the CentOS 4.7 server without over riding my routing tables to make eth0 a more direct route than the eth1 route.
On 5.2 If I do the ping -I eth0 remotehost, and a tcpdump on eth0, the outbound ping will not be going out eth0, he overrides it and sends it out eth1. In fact, on CentOS 4.7 if I do not have a route to the remote network through the other server (turn proxy arp off on the 5.2 machine), I will get "Destination Host Unreachable". I would ideally like to get the 5.2 machine to behave the way the 4.7 machine does.
My real life application for this is that I have a CentOS server in a location that controls access to the Internet. There is another router on the netowrk that handles traffic back to our corporate office. the CentOS server also has the ability to get to the corporate office. I ping the corporate office through eth0 to find out if the link through the other router is indeed up and active. I want to make this a CentOS 5.2 server but alas, I can not tell if the other route is up or not.
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
just finished installing Centos5 and I had no problems installing it. But when I tried to connect to the internet, the trouble began.My network card is installed and the status is "OK". The network card is a "Realtek RTL 8168C(P)/8111C(P)".The status of the device said "Inactive" and when I tried to activate it, it came with an error: Failed; no link present. Check Cable?Now the cable is connected as it should be.So next step I did is put in a static IP. Now the activation works fine.However I still have no internet. I can't even ping to my router!I need some new drivers for my graphics card too, but first I need the network to work, than I can download other stuff..
I have a box at home that I've installed CentOS 5 on to. I'm new to Linux, so before connecting it up to the router I wanted to try and understand the network settings, so I connected it directly to my other PC with an RJ45 cable. From Windows 7 I can ping all known static IP addresses, but from Linux I can only ping the Linux addresses, not the Windows 7 one. Below are the TCP/IP IPv4 settings, all IPv6 settings are set to auto-assign.
Windows box (uses wireless connection for the router): Local Ethernet Adapter IP Address: 220.127.116.11 Subnet: 255.255.0.0 No gateway, primary/secondary DNS.
Linux box: Three adapters: Two onboard LAN, both configured to: IP Address: 18.104.22.168 / 22.214.171.124 Subnet: 255.255.0.0 Gateway: 126.96.36.199 No primary/secondary DNS.
One LinkSys PCI card: IP Address: 188.8.131.52 Subnet: 255.255.255.0 Gateway: 192.168.1.1 (my router) Primary/Secondary DNS: my ISPs details.
The idea was to connect the box directly to the router (with RJ45) and to be able to remote login from my main PC to this one. This box is to be my home server, which I was going to put virtual machines on to for things like my development work and such.
In my office i have a network of 172.16.31.0 and a squid proxy server running, all other systems have windows XP and one system has centos. On centos system i have three lan cards and i want to test some things on it. So i assigned another IP on it of range 192.168.7.0/24 and same range on another windows system. And all the systems connected through a same network switch.
Unable to ping between Centos and Windows system. If i ping from one centos to windows system with the series of 172.16.31.0 then it replies very well but same thing is not happening in other 192.168.7.0/24 IP series.
I just downloaded and installed the latest Cent OS 5. I disabled SE linux, turned off the firewall, and selected the Server package options when installing. I plan on using this as a router/firewall between my internal network and the internet, as well as web server, etc. The first thing I did was to configure the two NICs, internal one with 192.168.7.1 address and the other with an address from my ISP (I have a static address, but I also tried to let the DSL router assign an address via DHCP). Everything looked fine, I checked /etc/resolv.conf and my routes. I was able to ping the DSL router from the server, but I was not able to do a ping or lookup on anything outside my network. I tried host, dig, nslookup, etc, no luck. Obviously then, I was not able to browse the net with firefox.
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.
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 a problem on my LAN, then: I have a laptop on which Windows Vista is installed, and every time I try to do ping to my server centos, my centos server does not respond to ping. The server is operating normally, because I found other PCs on my network that communicate normally with my centos server.
I have a box that I installed Elastix on as I'm trying my hand at Voip and Linux. I'm basically very green when it comes to Linux and the console. As I was following a guide @ engineertim.com to securing the box, it asked me to: wget [URL], But I get: Resolving engineertim.com... failed: Temporary failure in name resolution. I searched around and tried configuring resolv.conf to no resolve - :) unintended pun
I changed /etc/sysconfig/network to include GATEWAY=192.168.1.1 From the internet I have a modem-192.168.2.1, a telecom voip box-192.168.15.1, and then my router 192.168.1.1 I'm able to ping machines attached to the router but nothing beyond that. I tried to get the results for ifconfig via putty on this machine but it says command not found. I can get it when I log in at the box in question though.
I have a Lan with 100 computers with microsoft windows xp and vista on it, and I need to build a CentOS Primary domain control- PDC. So I am building a PDC , with samba 3.x +Ldap ( Light Directory Acess Protocol), with static eth0 and DHCP-server( Dynamic Host Control Protocol) on eth1. Eth0 : 192.168.1.3 Eth1 : 192.168.1.5
Here is the configurations files: == BEGIN uname -rmi == 2.6.18-194.17.4.el5 x86_64 x86_64 == END uname -rmi ==
== BEGIN rpm -q centos-release == centos-release-5-5.el5.centos == END rpm -q centos-release ==
== BEGIN cat /etc/redhat-release == CentOS release 5.5 (Final) == END cat /etc/redhat-release ==
== BEGIN getenforce == Permissive == END getenforce ==
== BEGIN rpm -q yum rpm python == yum-3.2.22-26.el5.centos rpm-184.108.40.206-20.el5_5.1 python-2.4.3-27.el5 == END rpm -q yum rpm python == == BEGIN ifconfig -a == .....
LAN CentOS 5.5 Windows 7 machine (hostname/NETBIOS name: AwesomePC, LAN IP: 192.168.1.20) Workgroup: Cake No WINS server No Domain No AD
From CentOS 5.5, have
# ping AwesomePC
resolve to a ping on 192.168.1.20
# ping AwesomePC
resolves to some random public IP that seems to be coming from my WAN DNS (openDNS) servers
Have edited /etc/nsswitch.conf, edited line: hosts: files wins dns Have edited /etc/resolv.conf, added line: search CAKE Have installed samba (# yum install samba) and run (# service smb start), with /etc/samba/smb.conf, workgroup = CAKE, name resolve order = wins host lmhosts bcast
Does # ping even care about samba? How can I get this to work?
I am using centOS 5.0. After I change from DHCP to static IP address, I cannot ping hosts on the same subnet. The error message says destination host unreachable. Before I made the changes I was able to ping and now even I change it back to DHCP I still cannot ping with the same destination host unreachable message. The centOS is running on VMware on a Windows host.
After pinging 192.168.0.106 (106 is on and other host can ping it), arp -a shows ? (192.168.0.106) at <incomplete> on eth0 I tried different ways by disabling the firewall and and disabling SE protection. No Luck.
I run an centos server. From the console I can ping google.com and get a reply. But when I ping another address say xyz.com, the IP address is resolved (220.127.116.11) but there is no reply. In the same network in our office from my desktop I ping [URL] and there is a reply.I turned of the firewall but still the same problem.
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 have a dedicated host on my lan to monitor other hosts/services using Nagios. I'm in the process of migrating to Zabbix on that host to perform the same purpose. Both Nagios and Zabbix monitor icmp ping latency (Nagios uses ping, Zabbix uses fping) and over time the latency to other hosts grows until threshold alarms are triggered. In one week, the average latency grows from sub-millisecond to over 100 milliseconds, and continues to grow until the Nagios host is rebooted. I have verified the latency numbers using ping/fping from the command line on the Nagios host.
The problem is that pings from the monitored hosts to the Nagios host show normal latency at the time the Nagios host is showing high latency from itself to the monitored hosts. The Nagios host and monitored hosts are all connected to the same Dell 24 port gigabit switch. I already posted this question on the Zabbix forums with a graph of the latency but there were no answers. [URL] why the icmp ping latency is growing over time and how I can fix it short of rebooting the host on a schedule.
I just installed my first EVER bind DNS server. I am running bind9 on Ubuntu 10.04. Everything seems to be working great except one thing: If I ping a host that I have set up in bind by its HOSTNAME the pings take 5-6 seconds to reply/print to the screen between each echo response. If I ping by the host's IP address, they echo back very quickly.
I have read that IPv6 can cause this, but I have disabled it in /etc/sysctl.conf and the problem still exists.
I know everyone says this can't be a DNS issue, but this never was an issue with dnsmasq (which i was using prior), and it doesn't make sense that the ping are ONLY slow when pinging by hostname and not IP.
Ping by hostname - there is a 5-6 second delay between each one of the responses:
Ping by IP - the responses come VERY quickly one after the other:
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 have Mandriva One 2009.0 (192.168.1.100) on one box and Mandriva Free 2010.0 (192.168.1.118) on the other. I can ping router (192.168.1.1) from both of these boxes but I can't ping one box to the other and the other way around. What's going on?.
Do I have to change some settings in router?. Or is it firewall issue on those two machines?. Both of these boxes are connected by cable. Symbol of the router: TL-WR340G.
I'm running CentOS V5.5. I am intererested in several packages available under RHEL V5. Is it possible to install these directly into CentOS or should I be looking for a package built for CentOS 5 specifically?
How does yum determine to "upgrade" an rpm verses "install" (and possibly delete) a package when performing a yum update? I have read documentation that yum uses the "Obsolete" and "Conflicts" tags within the rpm to determine whether to upgrade or install a new rpm. Is this correct and complete? I recall from somewhere kernel rpms should always be installed and never upgraded. How does yum determine that kernel rpms need to be installed using rpm -i as opposed to rpm -U? I have scanned a kernel spec file looking for clues without any luck.
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?