Jon Reeves's questions

I recently had a package signing key expire preventing some automatic updates from installing so am now setting up monitoring to make sure we are alerted if this happens again.

On Debian systems I can use apt-key to show all the repo keys and their expiry dates (if any) but cannot find how to do the equivalent for yum on CentOS

I can get some key info using:

rpm -q gpg-pubkey --qf '%{NAME}-%{VERSION}-%{RELEASE}\t%{SUMMARY}\n'

But this does not show expiry dates - any idea how to extract this information?

I am writing a script to carry out maintenance on several virtual machines running on Hyper-V

As part of this, I need to stop the VMs but if there is any kind of problem with stopping them, I want to abort the process

Problem is, Stop-VM prompts for confirmation if it encounters any problems and there doesn't seem to be any way to automate a response (there are no switches to the cmdlet to control what happens in these cases, -confirm:$false doesn't work, -force is the opposite of what I want, and sending STDIN to the cmdlet gives an error as it expects to receive a virtual machine via the pipeline

As an example, if the integration services are unavailable you get prompted to force a shutdown, which I would want to answer No to:

> stop-vm testvm01

    Confirm

    Hyper-V can't shut down virtual machine "testvm01" because the Shutdown integration service is unavailable. You can turn off the virtual machine by selecting [Y]es, but this is similar to pulling the power on a physical machine. To avoid potential data loss, select

    [N]o, then pause or save the virtual machine. Do you want to turn off the virtual machine?

    [Y] Yes  [A] Yes to All  [N] No  [L] No to All  [S] Suspend  [?] Help (default is "Y"): 

How can I script a response to this prompt?

Got a really frustrating problem with one of my clients systems. They regularly create Excel spreadsheets with loads of hyperlinks to other files in. Intermittently when they do this the open file dialog that appears when choosing to insert a hyperlink hangs for 30 seconds to a minute.

This will work fine for several days and then all of a sudden it won't work for a few days. It happens with multiple files in different locations for different users.

Terminal server 2008 environment with Office 2010 and files stored on mapped network drives

Things checked for/tried so far:

• Removed any invalid shortcuts in the affected folders
• Got user to log off and back on to ensure drives connected properly
• Increased idle timeouts on network drives
• Disabled "Robustified UNC"
• Disabled automatic hyperlink formatting
• Disabled anti-virus

Everything I can find points to dodgy shortcuts or disconnected network drives but this does not seem to be the case here.

Any suggestions greatly appreciated.

I'm currently studying for the Cisco switching exam and having trouble understanding exactly how 802.1q tagging works.

Given three daisy chained switches (A,B, and C) with trunk ports between them and VLAN 101 defined on both end switches (A and C), I'm not sure why the VLAN also needs to be defined on the middle one (B)?

Note that I am not disputing that it does need to be configured, I'm just trying to understand why exactly.

As I understand it, traffic from VLAN 101 on switch A will be tagged as it goes through the trunk to switch B. According to the documentation I have read, trunks will pass all VLANs by default, and the .1q tag is only removed when the frame leaves through an access port on the relevant VLAN. From this I would expect switch B to simply forward the tagged frame unchanged through the trunk to switch C.

Can anyone shed some light on how switch B processes this frame and why it does not get forwarded through the other trunk ?