Lately I've been coming across customer premise devices that appear connected, Wireless client associated to the AP and their PPPoE session is active, but unable to ping to internet devices.

The customer premise devices are setup as routers RB411 or RB711 boards configured with PPPoE interface, NAT, and DHCP server basic router config.

When the problem occurs the customer can not access the internet. When trying to ping from the device the error provided is there is no route to host. When trying to print the route table from the console the console just hangs and never displays anything.

This customer premise unit was running RouterOS 5.2, I've just upgraded the firmware on the routerboard and the RouterOS version to 2.35 and 5.5 respectively.

I simple reboot of the device would fix the problem, but it appears theres something with the route package/service that is getting hung up from time to time. This is about the 3rd or 4th time I've run across this problem. Each time I've upgraded to the latest Router OS version. I'm not sure if this is a permanent fix, but wanted to check with the community to see if anyone else has seen this issue.

I don't show any fix related to this problem in the change logs for later revisions of RouterOS. If anyone has seen this and can confirm it was fix by upgrading that would be appreciated.

Sound to me like pretty much exactly like the error say. No route. What i have found is that if you add encryption, this happens from time to time. Our clients recon the lost there security key and power the Rb down for few seconds. This happened especially with heavy weather. Have changed the setup and disabled encryption, and this problem disappeared.

Yeah.. That's not the problem. There's no encryption involved.

And I agree, the error message is pretty clear. The problem is the whole "/ip route ..." section of Router OS is unavailable when the problem occurs... Kind of like the routing service of the operating system is hung up. Rebooting solves...

Anyway I was just checking to see if anyone else has seen this. Has only happened a handful of times so I'm just going to chalk it up as some glitch that was fixed in the most recent version of 5.x.

5.2 had this problem for us.
Upgrade to 5.4 or 5.5.

This will fix your problem.