Fix found for Google Maps Tiling problem!
Problem: Google maps will not always show a complete map or satellite image. Random tiles will remain grey and will have a message (incorrect) that you need to zoom out because the level of detail is not available. ("no data for this level")
I chased this for a long time! Some fixes attributed it to java problems, others to various active X components (but it did not work in both Firefox and IE!). Some computers on my network reacted worse than others, so I missed the real culprit: the router/firewall.
The actual problem is caused by the firewall portion of the router (software firewalls can have this problem too!). Various routers have a portion to prevent SYN Flood attacks. Google Maps uses several servers with multiple threads, which can be recognized by the firewall as a SYN Flood.
The fix for my SMC firewall (this showed SYN flood in its logs BTW) was to either turn off “SPI and Anti-dos firewall protection” or in the Firewall/Intrusion Detection area to change “Maximum Incomplete TCP/UDP sessions from same host” from the default 10 to 99.
Some other routers call things:
network.http.max-persistent-connections-per-server
Others have mentioned similar problems with Belkin and Netgear Routers.
More SYN flood info at:
Problem: Google maps will not always show a complete map or satellite image. Random tiles will remain grey and will have a message (incorrect) that you need to zoom out because the level of detail is not available. ("no data for this level")
I chased this for a long time! Some fixes attributed it to java problems, others to various active X components (but it did not work in both Firefox and IE!). Some computers on my network reacted worse than others, so I missed the real culprit: the router/firewall.
The actual problem is caused by the firewall portion of the router (software firewalls can have this problem too!). Various routers have a portion to prevent SYN Flood attacks. Google Maps uses several servers with multiple threads, which can be recognized by the firewall as a SYN Flood.
The fix for my SMC firewall (this showed SYN flood in its logs BTW) was to either turn off “SPI and Anti-dos firewall protection” or in the Firewall/Intrusion Detection area to change “Maximum Incomplete TCP/UDP sessions from same host” from the default 10 to 99.
Some other routers call things:
network.http.max-persistent-connections-per-server
Others have mentioned similar problems with Belkin and Netgear Routers.
More SYN flood info at:
