Microsoft’s Tuesday patch-fest may have reacted quite negatively with Windows Server 2008 R2 running VMware, leaving servers offline and administrators scrambling to recover IP addresses.
Twitter user @Sikorsky78 noted the problem just after the patches hit:
Before long, the forums were alive with harassed sys admins dealing with similar problems, with a number of Reddit threads springing up discussing the issue.
The problem appears to afflict machines configured with static IP addresses.
During the installation of the update the NIC is replaced by another configured for DHCP, potentially knocking the machine off the network.
Administrators are reporting that rectifying the problem requires a little more effort than simply switching back from DHCP since the original NIC may still be present, just hidden.
Microsoft has remained tightlipped on the issue, leaving it to users to work out what part of the update borked their carefully crafted networks.
Reddit user “insufficient_funds” told The Register that test servers had been affected and posted a log file showing the NICs disappearing with the installation of KB4088875.
KB4088875 is a patch targeting systems running Windows 7 Service Pack 1 and Windows Server 2008 R2 Service Pack 1 and, as well as Internet Explorer fixes, includes Spectre and Meltdown patches and security updates for Microsoft’s virtualisation technology, Hyper-V.
Users are also reporting issues with KB4088878, which is a security-only update targeting the same configurations.
The issue appears isolated to Windows Server 2008 R2 installations, with those running VMware VMs particularly hard hit.
There are reports of Windows 7 users also experiencing problems with lost static IP addresses and vNICs.
It all sounds worryingly familiar to the first known issue with Microsoft’s inconvenience update for Windows 7 SP1 and Windows Server 2008 R2 SP1 when Microsoft said:
“A new Ethernet virtual Network Interface Card (vNIC) may be created with default settings in place of the previously existing vNIC, causing network issues. Any custom settings on the previous vNIC are still persisted in the registry but unused.”
The bulletin went on to provide a
vbscript file for administrators to run. Because administrators just love running
vbscript files on their installations.
“We’re aware of reports and are working to address,” a Microsoft spokesperson told us.
In the meantime, probably best to think very carefully before allowing these patches anywhere near a production environment, m’kay? ®