This post made my work easy yesterday – https://www.vladan.fr/check-esxi-logs-from-web-browser/
tl;dr version: go to https://IP_of_Your_ESXi/host.
 © Rakhesh Sasidharan |
I decided to take a break from my NSX reading and just go ahead and set up a VXLAN in my test lab. Just go with a hunch of what I think the options should be based on what the menus ask me and what I have read so far. Take a leap! :)
*Ahem* The above is actually incorrect, and I am an idiot. A super huge idiot! Each VM is actually just pinging itself and not the other. Unbelievable! And to think that I got all excited thinking I managed to do something without reading the docs etc. The steps below are incomplete. I should just delete this post, but I wrote this much and had a moment of excitement that day … so am just leaving it as it is with this note. Above we have two OpenBSD VMs running in my nested EXIi hypervisors.
And that’s where I am so far. After doing this I went through the chapter for configuring VXLAN in the install guide and I was pretty much on the right track. Take a look at that chapter for more screenshots and info. Yay, my first VXLAN! :o) p.s. I went ahead with OpenBSD in my nested environment coz (a) I like OpenBSD (though I have never got to play around much with it); (b) it has a simple & fast install process and I am familiar with it; (c) the ISO file is small, so doesn’t take much space in my ISO library; (d) OpenBSD comes with VMware tools as part of the kernel, so nothing additional to install; (e) I so love that it still has a simple
p.p.s. Remember to disable the PF firewall via Yay again! :o) Update: Short-lived excitement sadly. A while later the VMs stopped communicating. Turns out VMware Workstation doesn’t support MTU larger than 1500 bytes, and VXLAN requires 1600 byte. So the VTEP interfaces of both ESXi hosts are unable to talk to each other. Bummer! Update 2: I finally got this working. Turns out I had missed some stuff; and also I had to make some changes to allows VMware Workstation to with larger MTU sizes. I’ll blog this in a later post. The other day I blogged about how I had a host whose vMotion VMkernel interface seemed to be broken. Any vMotion attempts to it would hang at 14%. At that time I logged on to the destination host, then used The VMKernel interface is backed by two physical NICs. I found that if I remove one of the physical NICs from the VMkernel it works. Interestingly this link wasn’t showing any CDP info either, so it looked like something was wrong with it (the physical NIC shows as unclaimed coz the screenshot was taken after I moved it to unclaimed).
The reason why it failed is that by default network failover detection is via “Link status only”. This only detects failures to the link – like say the cable is broken, the switch is down, or the NIC has failed – while failures such as the link being connected but blocked by switch are not detected. In my case as you can see from the screenshot above the link status is connected – so the host doesn’t consider the link failed even though it isn’t actually working, thus continues to use it. Next I discovered that other hosts too similarly had their second vMotion physical NIC in a failed state as above yet they weren’t failing like this host. The simple explanation for this is that the host above somehow selected the faulty physical NIC as the one to use, didn’t detect it as failed and so continued to use it; whereas other hosts were more lucky and chose the physical NIC that works alright, so didn’t have any issues. I am not sure that’s the entire answer though. For once the host that failed was ESXi 5.5 and using a distributed switch, while the other two hosts were ESXi 4.0 and using standard switches. Did that make a difference? The default load balancing method for both standard and distributed switches is the same. (For a standard switch you check this under the vSwitch properties on the host. For a distributed switch you check this under the portgroup in the Networking section of vSphere (web) client).
I am still not sure of an answer but I have my theory. My theory is that since a distributed switch is across multiple hosts the load balancing method (above) of choosing a route based on virtual port ID comes into play. Here’s screenshots from two of my hosts connected to the same distributed switch port group for instance:
But what about a standard switch? Since the standard switch is only on the host, and the only VMkernel NIC connected to it (in the case of vMotion) is the single VMKernel NIC I have assigned for vMotion, there is no load balancing algorithm coming into play! If, instead of a VMkernel I had a Virtual Machine network, then the virtual port number matters because there are multiple VMs connecting to the various port numbers; but that doesn’t matter for VMkernel NICs as there is only one of them. And so my theory is that for a VMkernel NIC (such as vMotion) backed by multiple physical NICs and using the default load balancing algorithm of virtual port ID – all traffic by default goes into one of the physical NICs and the other physical NIC is never used unless the chosen one fails. And that is why my hosts using the standard switches were always using the same physical NIC (am guessing the lower numbered one as that’s what both hosts chose) while hosts using distributed switches would have chosen different physical NICs per host. That’s all! Just thought I’d put this out there in case anyone else has the same question. Was creating / migrating some ESXi hosts during the week and came across the above error “
By default the command only outputs the default gateway but you can pass it the
In my case the above output was from one of the hosts, while the following was from the non-compliant host:
Notice the To fix that I thought I’ll remove the The host didn’t have the
After that, removing the VMkernel interface can be done by a variant of same command:
Now I could add the re-add the interface via vSphere and get the hosts into compliance. Before I conclude this post though, a few notes on the commands above. If you have PowerCLI installed you can run all the
If I wanted to remove the interface via PowerCLI the command would be slightly different:
I would have written more on the
Heck you can even use The
If that VM were stuck for some reason and cannot be stopped or restarted via vSphere it’s very useful to know the
Regarding the type of killing you can do:
Another command line option is Lastly there’s also a bunch of
I haven’t used these much. They seem to be present for compatibility reasons with ESXi 3.x and prior. Back then you had commands with a That’s all for now! Update: Thought I’d use this post to keep track of other useful commands. To get IPv4 addresses details:
Replace with To set an IPv4 address:
To ping an address from the host:
Change keyboard layout:Get current keyboard layout:
List available layouts:
Set a new layout:
Remotely enable SSHThe To list the services:
To enable SSH and the ESXi shell:
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