- Windows Server 2008 R2 64 bit, running inside Xen 6.1.
- Updated to the latest Xen Citrix Tools for Windows.
- Disabled IPv6.
Currently trying to resolve the following:
- IIS FTP server works after a fresh reboot for approx. 2-3 days.
- After that, connecting to the FTP server is answered with an error (see below).
- Restarting the FTP site within IIS Manager results in a hanging MMC.
The FTP connection attempt (via FileZilla) is answered with:
ECONNREFUSED - Connection refused by server
- All other services like the side-by-side installed Apache server or the WWW part of the IIS work completely normally.
- No (in my opinion) suitable/any entries in the event log.
- No entries in the FTP log.
- An IISRESET call from the command line works correctly, without any error (it does not resolve the FTP issue, though).
My questions are:
- Any hints how to further find out in which "layer" this occurs (IIS, OS, HW, Xen)?
- Is there any chance that this is caused by the Xen environment/drivers?
Of course, I also would like to hear ideas on how to resolve, if you have any.
As of request, I started
netstat -ano | find ":21" on the server which results in:
TCP 188.8.131.52:21 184.108.40.206:52141 CLOSE_WAIT 1184 TCP 220.127.116.11:21 18.104.22.168:52146 CLOSE_WAIT 1184 TCP 22.214.171.124:21 126.96.36.199:52148 CLOSE_WAIT 1184 TCP 188.8.131.52:21 184.108.40.206:52149 CLOSE_WAIT 1184
220.127.116.11 is the IIS FTP server's public IP address, 18.104.22.168 is my local PC's public IP address (through our company gateway).
I'll now investigate further on how to interpret these results...
Running the same on a different webserver that has successful IIS FTP, these results look different:
TCP 0.0.0.0:21 0.0.0.0:0 LISTENING 1196 TCP 22.214.171.124:21 126.96.36.199:47746 ESTABLISHED 1196 TCP [::]:21 [::]:0 LISTENING 1196
Seems that my faulting server does not close the connections correctly?