Dropping Windows mapped network drives between guest and host

[Jackrh]

I'm able to map a network drive from inside a guest OS to a shared host folder, but after a short time, the drive mapping is dropped, and can't be restored without rebooting the host. I can still access the internet from the guest OS, and even ping the host, so the network appears to remain functional. The condition appears to affect all guests, so that if drives mapped to the host are dropped in one guest, they're dropped in all guests. However, I'm still able to maintain mapped drives between guests.

Workstation 6.5.1

Host OS - Vista 64

Guest OS - Windows XP Pro 32, bridged network

The VMWare bridged network is connected to the only enabled NIC on the system.

I've read about others experiencing a similar problem, but haven't seen any fixes. I tried networking the guests with NAT, and the problem seemed to go away, but NAT doesn't meet my needs.

Any suggestions would be more than appreciated. Being able to map drives to the host is crucial to how I need to work.

Thanks - Jack

[Scissor]

Try installing the latest driver for your Marvell Yukon NIC card on your Host. ( http://www.marvell.com/drivers/search.do )

On the advanced properties for your Marvell Yukon NIC card, try temporarily disabling any "Large Send Offload", "Task Offload", "LSO", or other "offload" features to see if it makes a difference.

What anti-virus/firewall software are you using? If you're running a 3rd party firewall you might need to make some sort of exception for the vmware-vmx.exe process.

Let me know how it turns out!

[fpiette]

I have the same symptoms altough I use Vista 32 bits as host. See my message titled "Network issue between host and guest". Actually you have the second issue I describe in my message: network shares located on the host are lost.

To Scissor: My network card (Intel wireless) has no "offload" option to turn off.

--

Francois Piette

http://www.overbyte.be

[Scissor]

I have the same symptoms altough I use Vista 32 bits as host. See my message titled "Network issue between host and guest". Actually you have the second issue I describe in my message: network shares located on the host are lost.

To Scissor: My network card (Intel wireless) has no "offload" option to turn off.

Hi Francois,

Your other thread had a suggestion to try and reproduce the problem using a wired connection. Were you able to reproduce the problem using a wired connection? Actually, I'll post a reply in your thread to keep things separated. ( Francois' thread is here: http://communities.vmware.com/thread/186574?tstart=0 )

[Jackrh]

I installed the latest Marvell driver, and disabled all "offload" features. I haven't run into any dropped mapped drives yet, but the speed is so slow now in one direction that mapped drives are now almost useless. Copying files from the host to guest (via mapped drives) is reasonable, but copying files from guest to host is too slow to use. For example, copying a 300MB directory to the guest takes about 30 secs, but copying the same directory from guest to host takes 15-20 mins.

I'm flagging this thread as answered because the original problem is resolved, but I'm still stuck without a workable solution for using mapped network drives.

Thanks for the responses.

[Scissor]

I installed the latest Marvell driver, and disabled all "offload" features. I haven't run into any dropped mapped drives yet, but the speed is so slow now in one direction that mapped drives are now almost useless. Copying files from the host to guest (via mapped drives) is reasonable, but copying files from guest to host is too slow to use. For example, copying a 300MB directory to the guest takes about 30 secs, but copying the same directory from guest to host takes 15-20 mins.

What an interesting result! Can you try enabling the "offload" features to see if the newer driver was all that you needed in order to fix the problem? Or, perhaps determine if only one of the "offload" features is causing the problem so that you can reenable the others?

[Scissor]

Another thing -- I noticed that your Guest is configured with 2 vCPUs. Unless your host has more than 2 cores you shouldn't configure a Guest with 2 vCPUs.

Try changing your Guest to a single vCPU to see if that helps with any slowness problems.

[Jackrh]

I will definitely try changing the number of vCPUs to see if has any impact. I do know that the VM I'm testing runs noticeably faster with 2 vCPUs, but I made that comparison before I noticed the problems with the mapped drives.

FYI - I'm running an Intel Core2 quad core CPU Q9550 @ 2.83 GHz in an Asus P5Q mobo with 8 GB RAM. No guest has more than 2 vCPUs. This system is (hopefully) replacing multiple multi-boot systems that I use for development work for different clients. I need separate systems for testing, and to keep different development platforms from corrupting each other. It's unlikely that I'll be running more than 2 or 3 VM's at the same time.

Thanks

[Jackrh]

Another good suggestion. I don't suppose that you have a link to somewhere with a good explanation of what each NIC setting does?

Thanks

[Scissor]

I will definitely try changing the number of vCPUs to see if has any impact. I do know that the VM I'm testing runs noticeably faster with 2 vCPUs, but I made that comparison before I noticed the problems with the mapped drives. FYI - I'm running an Intel Core2 quad core CPU Q9550

Crud -- I don't know where I got the mistaken idea that your host was a dual core system. Since you have 4 cores in your Host, then running a Guest with 2 vCPUs shouldn't be a problem. Sorry about that.

[Scissor]

Another good suggestion. I don't suppose that you have a link to somewhere with a good explanation of what each NIC setting does?

Not really.. it seems like each NIC Driver likes to call features by different names.

Here is a wikipedia link for Large Segment Offload: http://en.wikipedia.org/wiki/Large_segment_offload

...and here is a MSFT link from 2001 describing Task Offloading: http://www.microsoft.com/whdc/device/network/taskoffload.mspx

...and here is a MSFT KB article regarding possible performance problems with LSO and XP SP2 Firewall that is interesting: http://support.microsoft.com/default.aspx/kb/842264