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vijay_0812
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After I have changed Duplex setting of NIC of Service console, I am not able to connect ESX Host

Hi All,

Please help to resolve my issue.

After I have changed Duplex setting of NIC of Service console, I am not able to connect ESX Host .How can i reset duplex of NIC to back to 100 MB. Can anyone help me please.

Regards

Vijay

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Texiwill
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Hello,

As lightbulb stated you have two issues that are unrelated.

1) Duplex setting, your switch and NIC must match up. If one is set to autonegotiate then so shall the other be set to autonegotiate. Personally I tend to leave it autonegotiate unless there is an absolute reason to switch. If you do then switch both sides of the interface, switch port and use esxcfg-nics to change duplex, etc.

2) Passwords for root are unrelated to network unless you also ran esxcfg-auth to have it authenticate remotely. The only time I have seen what you have here is when the system is setup to try and authenticate remotely and not locally.

Both problems are fixable by booting into single user mode, fix the duplex and reset the password.


Best regards,
Edward L. Haletky
VMware Communities User Moderator
====
Author of the book 'VMWare ESX Server in the Enterprise: Planning and Securing Virtualization Servers', Copyright 2008 Pearson Education.
Blue Gears and SearchVMware Pro Blogs -- Top Virtualization Security Links -- Virtualization Security Round Table Podcast

--
Edward L. Haletky
vExpert XIV: 2009-2023,
VMTN Community Moderator
vSphere Upgrade Saga: https://www.astroarch.com/blogs
GitHub Repo: https://github.com/Texiwill

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oreeh
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Use the esxcfg-nics command in the service console.

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Troy_Clavell
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you will probably have to gain access to the ServiceConsole through some sort of remote access like iLO, DRAC, etc if you can't get to the physical hardware. Then you can change the duplex setting back.

an example would be

esxcfg-nics -s 100 -d full vmnic0

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vijay_0812
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Hi Oreeh,

But I am not able to login to Console even using root. Then how can i use this command. I am new to this technology. Please help me.

Regards

Vijay

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oreeh
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As Troy already mentioned you'll have to use something like Drac or ILO or you need access to the physical console.

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vijay_0812
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But the thing is I have ILO and Phisical access to the server, and also i am trying to login through ILO for console access and I tried give login credentials as before to login ESX host. But it is throwing me out.It remains show the lgoin prompt(i.e Login:)

It is not giving any message even like invalid login.

What might be the issue. please assist me.

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oreeh
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When logging in directly to ESX you have to use an ESX account (for example root) NOT an AD account (as you would with VC).

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vijay_0812
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I am using the root account (ESX Account) only to login. i dont have VC.

Thanks & Regards

Vijay

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oreeh
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In that case the only possible problem that comes to mind is a wrong password.

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vijay_0812
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Hi,

Just now I rebooted my ESX and went to Single user mode and reset the password and came back to MultiUser mode and tried new password. Still the same issue. It is not allowing me to login.

I have installed this ESX one hour before only . thats why i could able to reboot it.

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vijay_0812
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Can we reset the Duplex settings from Single user mode or is there any option? Please help me.

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Lightbulb
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If you installed the system 1 hour ago. It might be worth it just to reinstall. Given you have two issues with the current install might be easier to start from scratch. Just a thought.

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vijay_0812
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Hi All,

First, thank you for all to try to help me. Anyway, i started installing ESX again from starting. But , Is this the only solution for this type of issues?. Can u please help me. because its chalenging issue that may occur to any one.

Please let us know if you will find out solution for this isue in future.

Thanks in Advance.

Vijay

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Lightbulb
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In this instance you had two problems. One problem making it difficult to deal with the other. Your system was not production and in this instance a reinstall is the best use of you time. The suggestions made by everybody with regards to your Duplex issue were correct and usually would have been enough to get you going.

Sometimes quitting is the best option especially when you have a lot to do. I do not think you are likely to run into these exact issues again. Next time you may not have the option to just wipe and begin again.

Good luck to you.

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Texiwill
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Hello,

As lightbulb stated you have two issues that are unrelated.

1) Duplex setting, your switch and NIC must match up. If one is set to autonegotiate then so shall the other be set to autonegotiate. Personally I tend to leave it autonegotiate unless there is an absolute reason to switch. If you do then switch both sides of the interface, switch port and use esxcfg-nics to change duplex, etc.

2) Passwords for root are unrelated to network unless you also ran esxcfg-auth to have it authenticate remotely. The only time I have seen what you have here is when the system is setup to try and authenticate remotely and not locally.

Both problems are fixable by booting into single user mode, fix the duplex and reset the password.


Best regards,
Edward L. Haletky
VMware Communities User Moderator
====
Author of the book 'VMWare ESX Server in the Enterprise: Planning and Securing Virtualization Servers', Copyright 2008 Pearson Education.
Blue Gears and SearchVMware Pro Blogs -- Top Virtualization Security Links -- Virtualization Security Round Table Podcast

--
Edward L. Haletky
vExpert XIV: 2009-2023,
VMTN Community Moderator
vSphere Upgrade Saga: https://www.astroarch.com/blogs
GitHub Repo: https://github.com/Texiwill
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vijay_0812
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Hi,

Sorry for the late reply.

I have already re-installed my ESX server(production Box) again and it is now working fine.

However I have one Test Box and tried check the esxcfg-nics command in that test box through Single user mode as suggested by you. It was applied successfully. that means i was able to reset the duplex settings of my nic to 100 MBPS full duplex.

Note: I have run the following command after the installation. could it be the caused not to allowing me to login to ESX at that time in multi user mode?

esxcfg-auth -disablead -disableldap -disablekrb5.

also Can u please tell me the meeaning of above command?

Thanks for sharing the knowledge.

Regards

Vijay

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Texiwill
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Hello,

esxcfg-auth -disablead -disableldap -disablekrb5.

also Can u please tell me the meeaning of above command?

DIsabled Active Directory, LDAP, and Kerberos authentication modes, which are actually NOT enabled by default. However, I would not issue that command unless you enabled these three things in the beginning. It should have no issues, but I have not tried it as it modify /etc/pam.d/system-auth which could prevent you from logging in as root. I would have to see the resultant file to tell.


Best regards,
Edward L. Haletky
VMware Communities User Moderator
====
Author of the book 'VMWare ESX Server in the Enterprise: Planning and Securing Virtualization Servers', Copyright 2008 Pearson Education.
Blue Gears and SearchVMware Pro Blogs -- Top Virtualization Security Links -- Virtualization Security Round Table Podcast

--
Edward L. Haletky
vExpert XIV: 2009-2023,
VMTN Community Moderator
vSphere Upgrade Saga: https://www.astroarch.com/blogs
GitHub Repo: https://github.com/Texiwill
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