I have an RB5009 connected to Verizon FIOS internet for years now and it’s been working great.
All of a sudden, none of the computers on the LAN can access yahoo.com or finance.yahoo.com in any web browser.
This includes hardwired (cat6) computers to the 5009 as well as wifi-connected through an ax3.
All PCs can ping both sites just fine.
I rebooted the 5009 (which was running great for 149 days), but that did not fix it.
I tried both Chrome and Edge on several PCs (as well as Safari on the iPhone).
I even changed the DNS on the PCs to use 1.1.1.1 in case it was a DNS problem.
Given that the problem is occuring on all computers, wired and wifi, I think it’s reasonable to assume that the problem is with the 5009, or the cable modem, or Verizon, or with yahoo, right?
Any suggestions on how to proceed with troubleshooting?
I doubt it’s the RB5009 but I’ll concede that anything is possible. I would suggest you temporarily bypass the RB5009 with a single PC / laptop by plugging in directly to the Verizon FiOS ONT (it’s not a cable modem but we all know what you mean). If you can access the problematic Yahoo websites while plugged directly into the ONT, then consider sharing your RB5009 configuration so we can help you troubleshoot further. If you still can’t access the Yahoo sites while plugged in directly to the ONT, then the problem isn’t the RB5009.
Mysteries like this one often happen if the MTU in your network becomes smaller than the “usual” 1500 for some reason and PMTUD (Path MTU Discovery) is broken (google up “criminally braindead ISP” to learn the details) on the path between the client and the server.
So knowing about your other threads, I’d suggest you first check what is the value in the ACTUAL-MTU column in the output of interface print where name=bridge (substitute bridge by the actual name of your bridge interface if needed). If it is not 1500, chances are high that you’ve made at least one EoIP interface a member port of that bridge. The MTU of bridge interface is the minimum of the MTU values of all its member ports (you’ll get bonus points for an explanation why is that a good thing).
The bridge’s (named “BRIDGE”) Actual MTU was 1400.
I removed the 8 EoIP interfaces from the bridge, the Actual MTU automatically changed to 1500, and I now have access to yahoo.com
I see that the Actual MTU of the EoIP interfaces are either 1400 or 1416, so it makes sense that the bridge’s Actual MTU was 1400 (the lowest of all it’s member ports).
I don’t see any differences in the configs of those eoip interfaces to explain 1400 vs 1416.
Looks like I’ll be going with your advice from my other thread about keeping those eoip interfaces off the bridge.
This is a short but detailed thread on “criminally braindead IPS”:
That’s where selective thinking comes into play - the change (addition of the first EoIP interface to the bridge) was made so long before the issue with access to Yahoo got spotted that the relationship did not pop up immediately, and when thinking back, it was “just adding EoIP to the bridge, no tampering with firewall rules or so” - hence “it can’t be related”
Life hack: your ability to spot others’ mistakes grows rapidly as you make your own ones. In another words - been there, seen that.
sindy knows about another thread of mine where I was asking about (and therefore playing with) EoIP connections, so he correctly deduced that changes were made.
I don’t think I’ve ever made just 1 change. At the very least, there are multiple changes to a single config or a single coordinated change to 2 MT devices.
Nothing at all wrong with “been there, seen that” – I’ll be using it.
