Fedora 26 vm on Windows 10, wrong router MAC

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Fedora 26 vm on Windows 10, wrong router MAC

Postby Stavroche » 14. Sep 2017, 08:39

I'll explain as simple as I can and preface a couple things. I did search the forums in the forums, I searched Google, I also google specifying virtualbox site, 20 yrs doing this stuff but I don't know what's causing my problem.

Bridged connection, of course.

I was having connectivity issues, basically anything requiring routing, happened in Fedora and Ubuntu on the same Intel NUC system running VirtualBox and might have happened with Hyper-V desktop version but that had other issues so I got rid of that. Summing it up, my router has seemed faulty but it was expensive and I will replace but I have to wait a bit longer and searching everywhere showed others having similar problems but no clear solutions nor anyone listing the same source of the problem, the wrong MAC address for the router.

arp -a on the fedora showed this address combination for the router, not a copy of the output:

192.168.0.1 98:ee:cb:13:61:ba

that's not the right MAC for the router, not the MAC for the virtual NIC, not the MAC for the PC, not the MAC for anything on my network, looked it up in vendor tools got this:

MAC Address/OUI Vendor {Company}
98:EE:CB Wistron Infocomm (Zhongshan) Corporation

Say what? I don't know what that is, here's the Netgear MAC and what is should have, a0:63:91:d1:0c:88

I meant to delete the entry first and try again but I jumped the gun deleting the arp and adding the correct one, which I can again remove but that fixed it immediately as I knew it would.

What I have no idea about is where this fantasy MAC address is coming from this has never happened before. I have virtual CentOS on VMware, Hyper-V, KVM and it's always the same thing again as it should be they have the right MAC no reason to spoof that.

And the perm arp will fix it for good but that doesn't tell me the problem, and why it's like even though I have bridging selected and working mostly, as I always have with VirtualBox for the past 10 years, this behavior seems like it thinks it's suppost to do some NAT, Host only whatever?

Guys, gals I appreciate your time, sorry this was long, it's cursed me for weeks now and I had to vent. If you have any help or have seen it before and know why this is happening let me know.

This happens off a fresh install, no changes have been done to the fedora OS, not yet, just the arp entry, and mostly defaults with VBox settings, bridged networking? That's it.

Thanks
Stavroche
 
Posts: 4
Joined: 14. Sep 2017, 08:08

Re: Fedora 26 vm on Windows 10, wrong router MAC

Postby Stavroche » 14. Sep 2017, 10:57

I wanted to update this one, I created a work around, it's a permanent fix until possible update or distro upgrade wipes it out.

I still don't know why I have to do this, when the wrong MAC for the router exists or it's blank then Internet is broken. The router is 192.168.0.1 on the 192.168.0.0/24 network just to be clear, and after I replace my router I'll see if this is still happening.

Had to enable the arp-ethers.service, didn't want to modify any interface startup scripts, those will be overwritten and that's not really cool to do. Had to create the file /etc/ethers which enabling the service does not do but depends on to exist.

Had to make the service depend on network.service network.target and network-online.target, the last being most important, by default it doesn't do that and fails because the network isn't up when trying to add an arp.
Had to set it to Require the network.service so that if you restart the network.service or it gets restarted for whatever other reason it also restarts the arp-ethers.service, by default being dependent on a startup (After=) does not tell it to also restart. Still dumbfounded why I had to do any of this but I know I need to replace that router, but there's no reason why the real MAC shouldn't also be used, that's just not standard, so not sure what's happening there.

Here's the service file modifications, I'll highlight what I disabled, and what I added and I know this isn't a solution, just a work around.

1. systemctl enable arp-ethers.service
2. vi /usr/lib/systemd/system/arp-ethers.service

This is based on preference somewhat.
3. Commented out lines:
#After=network.service
#Before=network.target
4. Added these lines under Unit section:
Requires=network.service
After=network.service network.target network-online.target
5. Rebooted and problem will not happen again, correct entry is always in the arp table.

[root@FedDesk ~]# cat /usr/lib/systemd/system/arp-ethers.service
[Unit]
Description=Load static arp entries
Documentation=man:arp(8) man:ethers(5)
ConditionPathExists=/etc/ethers
#After=network.service
#Before=network.target

Requires=network.service
After=network.service network.target network-online.target


[Service]
Type=oneshot
ExecStart=/sbin/arp -f /etc/ethers
RemainAfterExit=yes

[Install]
WantedBy=multi-user.target

I may be away for a little but I'll check this I'm sure many on here that know VirtualBox very well might know more about this problem or the exact problem, but thanks for any current or future contributions.
Stavroche
 
Posts: 4
Joined: 14. Sep 2017, 08:08

Re: Fedora 26 vm on Windows 10, wrong router MAC

Postby Stavroche » 14. Sep 2017, 14:50

Last update for now, I also had the exact same problem on the latest Desktop version of Ubuntu, so I have Fedora and Ubuntu desktops as vms on Win 10, virtualbox.

I can include what I did on Ubuntu, latest version if anyone wants to know or needs this work around because even a bad router doesn't normally update the wrong arp entry, so weird.

I believe Microsoft Hyper-V on this computer had the same problem but I didn't verify if it had the wrong mac because there were other issues, Hyper-V not bad on Windows Server, bad on Windows desktop.

I saw other people had similar problems and never found a culprit such as the wrong router mac address so maybe this can help or maybe I'm the only one with this weird problem.

Shouldn't have to do static arps in 2017, never best practice for obvious reasons. Even if someone out there had a semi relevant or somewhat similar please let me know doesn't have to be the same problem but looking for anything to clear it up unless it's simply the router and retiring it will fix all, coming soon.
Stavroche
 
Posts: 4
Joined: 14. Sep 2017, 08:08

Re: Fedora 26 vm on Windows 10, wrong router MAC

Postby Stavroche » 16. Sep 2017, 19:07

Kind of resolved and boy do I feel like a big dummy. So I setup an old desktop next to the PC in question, next to the PC running VirtualBox, installed Ubuntu, same problem. Nothing to do with virtualization, hooked up directly to the router, no problem, it's the switch I use, it's an old junkie Netgear, one of those oddball 5 port ones, trash. Thanks for letting me spam everyone.
Stavroche
 
Posts: 4
Joined: 14. Sep 2017, 08:08


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