amaru96
asked on
Trouble with networking a Linux RedHat server
Hi guys, I have almost zero experience with Linux so please bear with me.
I've been asked to deploy a server running RedHat Enterprise 5 within our VmWare environment. I have installed RedHat and everything seems fine, However, I am unable to get the networking side of things to work properly.
I've assigned it an IP address and from the Linux server itself I can open up a terminal and ping itself but that is all I can ping. I can't ping anything else on the network, including other servers on the same subnet or the gateway.
I also tried changing it from using a static IP to DHCP. It receives an IP address from the DHCP server but again the same result. The server can ping itself but nothing else.
When I do try to ping another address it says "From myipaddress icmp_seq=1 Destination Host Unreachable"
Any advice would be much appreciated.
I've been asked to deploy a server running RedHat Enterprise 5 within our VmWare environment. I have installed RedHat and everything seems fine, However, I am unable to get the networking side of things to work properly.
I've assigned it an IP address and from the Linux server itself I can open up a terminal and ping itself but that is all I can ping. I can't ping anything else on the network, including other servers on the same subnet or the gateway.
I also tried changing it from using a static IP to DHCP. It receives an IP address from the DHCP server but again the same result. The server can ping itself but nothing else.
When I do try to ping another address it says "From myipaddress icmp_seq=1 Destination Host Unreachable"
Any advice would be much appreciated.
Whats the output of the following command
ethtool eth0
Note: You should be root to run this command successfully
ethtool eth0
Note: You should be root to run this command successfully
This sounds like it could possibly be connectivity related...
Check the VMWare network, make sure it's bridged with a physical adapter and that adapter is connected to the right switch/vlan.
If you've got a more complex VMWare network, with virtual switches and you're doing some tricky stuff there, that's something to check.
The linux installation sounds like its setup correctly from what you describe. However, if you have multiple virtual adapters assigned to the VM, you could possibly have configured the wrong adapter.
Also, it is possible the device type for your adapter has an issue, not sure what edition/version of vmware you are using, but if you have choices for the network adapter type, you might switch that up... This will cause you to have to reconfigure the network.
Be sure to have installed VMWare tools as well.
Check the VMWare network, make sure it's bridged with a physical adapter and that adapter is connected to the right switch/vlan.
If you've got a more complex VMWare network, with virtual switches and you're doing some tricky stuff there, that's something to check.
The linux installation sounds like its setup correctly from what you describe. However, if you have multiple virtual adapters assigned to the VM, you could possibly have configured the wrong adapter.
Also, it is possible the device type for your adapter has an issue, not sure what edition/version of vmware you are using, but if you have choices for the network adapter type, you might switch that up... This will cause you to have to reconfigure the network.
Be sure to have installed VMWare tools as well.
I concur with the above, but would look first at the gateway. Also, if I recall correctly, RedHat comes with a firewall configured. turn that off for troubleshooting with this series of commands (as root):
# iptables -F
# iptables -X
# iptables -t nat -F
# iptables -t nat -X
# iptables -t mangle -F
# iptables -t mangle -X
# iptables -P INPUT ACCEPT
# iptables -P OUTPUT ACCEPT
# iptables -F
# iptables -X
# iptables -t nat -F
# iptables -t nat -X
# iptables -t mangle -F
# iptables -t mangle -X
# iptables -P INPUT ACCEPT
# iptables -P OUTPUT ACCEPT
ASKER
It's running on vmware esx enviornment with multiple vlans. I have checked and it's on the right vlan.
I ran ethtool eth0, the result is:
Settings for eth0:
Link detected: yes
Also ran the firewall commands from mccracky with no change.
I install vmware tools too
The strange thing is that from my computer if I run a constant ping to the linux server it responds a handful of times as it boots. Once the boot sequence ends and it prompts for a username the reply stops!
I ran ethtool eth0, the result is:
Settings for eth0:
Link detected: yes
Also ran the firewall commands from mccracky with no change.
I install vmware tools too
The strange thing is that from my computer if I run a constant ping to the linux server it responds a handful of times as it boots. Once the boot sequence ends and it prompts for a username the reply stops!
run
service iptables stop
Just for grins... should do the same as iptables commands above... but...
service iptables stop
Just for grins... should do the same as iptables commands above... but...
ASKER
ran service iptables stop, no change
also disable selinux
setenforce 0
setenforce 0
ASKER
Ran setenforce 0, no change. Does it need a reboot?
Hi
When installing the Linux you dont need to make any special changes on the Network. Just add the IP and is working. If you did not change anything, then this is working on the Linux side.
Lets focus on the VMware ESX.
You say that you have some VLANs. Is this VM using a standalone vSwitch? Or is using a vSwitch that has other VMs?
Can you please explain your VMware networking on the VM side?
Jail
When installing the Linux you dont need to make any special changes on the Network. Just add the IP and is working. If you did not change anything, then this is working on the Linux side.
Lets focus on the VMware ESX.
You say that you have some VLANs. Is this VM using a standalone vSwitch? Or is using a vSwitch that has other VMs?
Can you please explain your VMware networking on the VM side?
Jail
ASKER CERTIFIED SOLUTION
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xend is the xen daemon for virtualization. Were you trying to run nested virtual machines? Virtual machines under linux with xen which itself runs in a virtual machine on vmware?
ASKER
No, I wasn't running a nested VM. I deployed a new VM on an ESX server and installed RedHat directly on it.
mccracky: is correct, this is a nested virtual machine by mistake, you probably installed RHEL as default and you are booting with the kernel-xen.
Do you have 2 options to boot from , when the machine first comes up hit any key you should get the boot menu, you might find that there are 2 kernels , kernel-2.6.9 and kernel-xen-6.2.9. make sure you don't boot the kernel xen.
If this is the case let me know so I help you change the boot order from Grub
Do you have 2 options to boot from , when the machine first comes up hit any key you should get the boot menu, you might find that there are 2 kernels , kernel-2.6.9 and kernel-xen-6.2.9. make sure you don't boot the kernel xen.
If this is the case let me know so I help you change the boot order from Grub
ASKER
I don't actually get a boot option, I start the VM and it loads up, no menu appears with a choice.
Appreciate all the suggestions and help from everyone.
Appreciate all the suggestions and help from everyone.
Hi
No warnings?? No errors??
Jail
No warnings?? No errors??
Jail
ASKER
Nope, boots up clean, no errors.
Hi
Are you sure? :)
Have you click on the screen console? Any movement?
Jail
Are you sure? :)
Have you click on the screen console? Any movement?
Jail
ASKER
Not sure what you mean?
The server boots up, RedHat loads and I can use it. I can also access it remotely.
The server boots up, RedHat loads and I can use it. I can also access it remotely.
Hi
Sorry I did not understand.
So what is the issue? The server work?
Jail
Sorry I did not understand.
So what is the issue? The server work?
Jail
Nothing we suggested even helped narrow down the issue? Non of our troubleshooting actually helped?
ASKER
Unfortunately not. I only discovered it by booting it in "interactive" mode and manually checking each service is it was brought online.
As I mentioned in one of my comments, I could ping the server while it boots but once it completed booting the replies stopped. So I knew something was changing or being executed during the boot up which prevented communications.
Only by chance did I see the message that said "Press I for interactive". I ran a continuous ping to the server as I slowly went through the services. It kept replying until I started the XEND service which then stopped. From that I figured the XEND service was in some way causing communication problems. I disabled the XEND service, rebooted and everything was fine, and still is.
Appreciate all the suggestions from everyone but they didn't really help solve my problem.
As I mentioned in one of my comments, I could ping the server while it boots but once it completed booting the replies stopped. So I knew something was changing or being executed during the boot up which prevented communications.
Only by chance did I see the message that said "Press I for interactive". I ran a continuous ping to the server as I slowly went through the services. It kept replying until I started the XEND service which then stopped. From that I figured the XEND service was in some way causing communication problems. I disabled the XEND service, rebooted and everything was fine, and still is.
Appreciate all the suggestions from everyone but they didn't really help solve my problem.
Ok, fair enough.
Hi
Since points will not cost you nothing, sometimes I cannot understand some users.
But thats me.
Jail
Since points will not cost you nothing, sometimes I cannot understand some users.
But thats me.
Jail
Restarting author's original action
SouthMod
Community Support Moderator
SouthMod
Community Support Moderator
First what VMware are you using? ESX?? Workstation/Server?
Since your have no experience in Linux, check this articles to double check you Linux configuration
http://www.yolinux.com/TUTORIALS/LinuxTutorialNetworking.html
http://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch03_:_Linux_Networking
Jail