VM console frozen putty session will not connect.

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I have a VM running red hat and the console is frozen at 6:15am. Try to do a putty session and it hangs never getting a root signon. I can ping the machine but that about it. CPU is at 100%, Memory is at 4% and disk at 0%.

Shutting down the VM, the bad way, seems the only option, are there other options if any?

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I am not sure if there are any options, but it would be helpful to know the following:
1. Which virtual graphics adapter is the guest using?
2. Which version of RHEL is the guest running?
3. Which version of RHEL is the host running?

I think I have seen this bug when using qxl graphics, but it was with an Ubuntu guest. (Ubuntu's qxl drivers seem very buggy.)

I've been testing for months virtualizing a system and now that I've gone live with my development host we keep experiencing the same issue roughly every two weeks. I'm running a standard video card, not sure whey I find the specifics but it's set to 1 display and 8m of video memory. This is RHEL 7 on the guest however I'm running on VMWare. Any suggestions? The best I can do is a hard power off.

Does anything get logged in syslog prior to the reboot? You mentioned memory was at 4% - was this value retrieved from the VMware console, or the host itself? I have seen this sort of thing stemming from a file system filling up and logging is no longer possible , or another situation where memory was not being reclaimed (you would see page allocation failures in syslog)even though the system appeared to have some memory/swap available - very odd problem.

I would consider looking at OOM killer and kdump. I don't recall if the VMware console has the ability to send SYSRQ - but I would also look in to How to use the SysRq facility to collect information from a server which has hung

Steven, just to rule out issues with putty, have you tried using the VMware console, then log in to some other server on the same subnet, then do an ssh from that server to the one you wish to connect to?

I've seen unexplained behavior from putty, such that if I visit (by ssh) to some other system, then ssh from the other system to the one you intend to go to, that helps sometimes.

I'm typically not using putty, however, I've seen this occur. Yes, that condition should not, that being said, it is worthwhile to check.

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