Strangeness with Linksys WRT54G

I had a weird problem for a few days on my home LAN, using a Linksys WRT54G v2 router (v4.20.7 µCode), tied to WAN via Moto SB 4200 to Comcast.

Symptom 1: Could not send or forward long (>1000 bytes) emails from Moz v1.7 on wired XP PRO PC: after ~60 Secs, Moz reported failure to connect to smtp server; but, short (

Reply to
Bob Willard
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Long timeouts like that sound more like there's gear UPSTREAM at the ISP that has to timeout, not this equipment. Try this, instead of powering it off, physically DISCONNECT it from the cable modem. Wait that 3 minute period, reconnect it and see if the "problem" went away. I'm guessing it will.

That being the case there are other debug steps to consider.

Reply to
Bill Kearney

Interesting. I can't tell the diff, since the router was both powered down and uncabled. And, the problem has gone away (for now).

Reply to
Bob Willard

Here's a thought, what other traffic was being routed through it? Is it an open wifi network? Might've been something else hammering a ton of traffic through the link and that tripped something on the ISP's side of things.

Reply to
Bill Kearney

The WiFi segment is secured with WPA, and usually pretty light anyway. The bulk of my LAN traffic is on the wired side, including a gamer (sometimes 2). But the traffic wasn't unusually heavy when the router went funny.

I'm holding my breath, to see if the router (or whatever) goes awry again. This Linksys router is ~3 years old, and the previous router (Linksys) lasted for ~5 years before the radio front-end died.

Reply to
Bob Willard

The current firmware version is 4.21.1.

There doesn't seem to be anything related to this problem in the release notes:

but methinks it's worth trying a firmware update anyway.

That's odd. You can connect to an SMTP server if you append a short message, but can't with a long message. The problem is that the initial SMTP connection is made *BEFORE* the message is sent. If it can't connect, it doesn't matter how long a message follows. Can you be more specific as to the error message?

weird. Look at the first setup page on the WRT54. What do you have for the MTU (maximum transfer unit)? For a cable modem, it should be

1500 bytes.

One possibility is that you have a sick router on the path between you and your SMTP server. Go unto:

and grab MTUROUTE.EXE v2.1. Run it and see if you can actually use

1500 bytes.

Same issue. Run MTUTROUTE pointing it to the web servers with problems. Compare with a web server that is close to your ISP and does not go through many other routers and spagetti.

It's possible. However, if there are any imparements involving SSL and encryption, you'll get a very different assortment of nasty error messages from the browser.

Weird 2.0. If it were an Max MTU problem, then it should show up on the downloads. However, that assumes that the downloads and the problem web sites go via the same router when leaving your ISP.

Smells like a buffer overflow problem in the router. Try the firmware update.

Yeah, it's weird. If you have another router, see if it does the same thing. That will at least determine if the router is at fault.

Reply to
Jeff Liebermann

And when it does remove the ethernet cable from it first and wait the 3+ minutes. Or longer. You do want to rule out that it's not something being blocked upstream.

Hmm, here's another suggestion, change the hardware MAC address of the WAN port. It's buried in the setup pages on the router. This would, effectively, make the upstream network think a new device had been attached. This probably won't do anything. It's more likely any upstream filtering (or whatever) is tied to the IP address more than the MAC. If you change it make sure to change it back.

If the disconnecting doesn't work, then try powering down the DSL modem for that same delay. Couldn't hurt to rule it out.

Reply to
Bill Kearney

It is not MTU; I've used MTU=1500 on the router and all PCs for years. And I only have one router in my LAN (I've stretched the 4-port LAN by using a hub to connect in 3 PCs that use the WAN sparingly).

Yeah, a buffer overflow fits. If it comes back, I may try to update the firmware, even though the firmware notes did not say anything about fixing this kind of problem.

Reply to
Bob Willard

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