Had a helpdesk logged by a teacher, saying she is unable to access prezi.com. On request for further information, I was told, she could get to the site, login fine, but was unable to create/edit presentations. An error stating;
There was a problem loading your prezi.
Please check your internet connection or firewall, and allow traffic to prezi.com. Also, please make sure you have the latest version of Flash.
After checking flash versions etc, and testing on other machines, I determined, that either going via RM Smartcache, or direct to of LEA Proxy, had the same result.
Next step was to look at our ISA box. After running a monitor on my attempts to access the site, I got the following
Failed Connection Attempt CLW-SR-ISA 15/06/2012 10:35:56
Log type: Web Proxy (Forward)
Status: 995 The I/O operation has been aborted because of either a thread exit or an application request.
Rule: SysAdmin PC External Access
Source: Internal (192.168.2.68)
Destination: External (184.108.40.206:80)
Filter information: Req ID: 0fd5205e; Compression: client=No, server=No, compress rate=0% decompress rate=0%
Client agent: Mozilla/5.0 (Windows NT 5.1; rv:12.0) Gecko/20100101 Firefox/12.0
Object source: Upstream (Object was returned from an upstream proxy cache.)
Cache info: 0x0
Processing time: 0 ms
Anyone had this before? or know what I could do to resolve?
Have you identified the 220.127.116.11 ip address? I don't need to know what it is but could it be your upstream proxy blocking as the destination is port 80 (http)and the site is requesting a 443 (https)
To me it looks like the upstream proxy is blocking the 443 request.
Have a word with the LEA providing the proxy I guess would be an idea.
That confuses me even more as we have supposedly had the LEA's firewall rules amended to allow access to all google servers, due to issues we had with Google Docs! I don't suppose you know which Google server?
Inspect your proxy logs for all outgoing connections from a client with Prezi loaded in the browser the moment the page refreshes. I've had sites pull content from servers by using an IP address instead of a domain name and our upstream proxy is setup to block browsing by IP. Placing that single IP on a white list usually fixes that.
Another issue I've seen is pretty much the same scenario, but the IP address keeps changing as the external content was hosted on a cloud service.