Darkavich's Daily Ramblings Ramblings of a Mad Sys-Admin

Ok, for the last 4 days I have been struggling with getting the iPhone mail client to work properly when on edge.

The client works perfectly when on WiFii, but failed to connect when on edge. There are lots of postings of other people having the same problem all over the country. Knowing a few things about networking 😉 I started troubleshooting.

I found that with an edge device we could telnet to my hosts on port 80 and port 25 (web and mail), but failed to connect on port 143 (imap). I ran several snoops and noticed that we could see the packets making it to my server, but the imap session never being established.

I was running the snoops so I could see what IP address the devices are coming from. When I saw the bizzare names, I decided to start doing some investigating and noticed that there was a reverse PTR record, but no forward A record.

% host mobile-032-162-049-101.mycingular.net.
Host mobile-032-162-049-101.mycingular.net not found: 3(NXDOMAIN)
% host 32.162.49.101
101.49.162.32.in-addr.arpa domain name pointer mobile-032-162-049-101.mycingular.net.

Well, this was the lightbulb I needed. imapd is launched from inetd, unlike mail and web. Mail and web both have a daemon running on their own. All of my inetd services like imapd are wrapped by tcp-wrappers. A quick look at the tcpd logs showed:

Jan 7 11:09:37 c130 imapd[19384]: [ID 140027 local6.error] warning: can’t verify hostname: gethostbyname(mobile-032-162-049-101.mycingular.net) failed
Jan 7 11:09:37 c130 imapd[19384]: [ID 947420 local6.warning] refused connect from 32.162.49.101

So the problem is both AT&T’s and mine. Because I use tcp-wrappers, the connecting hosts MUST have a valid A record for the PTR. The fact that AT&T doesn’t have valid A records is not playing nice on the internet.

Now the world is starting to make sense. Why does this work for some people and not others. The reason is because they are still using old IP’s from Cingular, and not the new ones from AT&T. It appears that all of the mycingular hosts are missing the forward lookups.

So, I have my workaround, but ultimately AT&T needs to fix this problem. I will still suggest you open a ticket with AT&T and ask them to fix their DNS records. Properly registering IP addresses that are used on the Internet is not only a polite thing to do, but also prevents things from breaking that rely on valid DNS records.

A few items today.

The speaker does not work well with noise in the room. It keeps cutting out. Not sure anything else could do any better though. I had my first lockup today. The phone would turn on but could not unlock it. It took me a bit to figure out how to reboot it, but all is back to normal. The first time this happens trying to answer a call will warrant a visit to the apple store.

This has been the only real issue so far. I am using edge as I type this on my iPhone. It tried to connect to an AT&T wifii but failed. My blog loaded pretty fast. Amazon was not so fast. So it’s still an unknown if edge is good or bad. More testing is needed.

Well, dinner has arrived so I am done for now. More details later.

So you can not SMS to more than one person at a time. This just seems silly. Is it possible they did this out of greed? On Verizon, when I send a text message to a group of people I am charged a single text message. Now I have to use three messages. I have heard rumors that this will be fixed in 1.1.3 firmware.

I have been totally unsuccessful in getting my email client to work over Edge. I have found “tons” of posts that tell me this is a common problem, with NO solutions. I have my theory this is a firewall issues and I have asked my inside contact at AT&T to see if he can find someone inside that has a clue.

I received an iPhone for my birthday! Angie got me one.

So far I have to say this is a very impressive device. I only have a few negatives and all of them can be fixed.

1) AT&T requires a physical street address when you activate the phone. There is zero reason that they need this. I need to see my first bill to make sure they mail it to my house. I thought about just not giving them a valid address, but figured it’s a binding contract and not worth the hassle.

2) Lack of internet chat client. the only chat client uses SMS. I am unable to chat with AIM/Yahoo/G-Talk users. This can be easily fixed by adding the ichat client to the phone.

3) Mail client is restricted to no more than every 15 minutes for checking email. I usually like to have it checked every 5 minutes.

As I mentioned all of these can be easily fixed. So far, those are the only complaints I have. That is very good for me, especially for a first generation product.

The positive things:

1) The phone works as a phone. It has not crashed or rebooted on me. I make a call, it calls, I can talk and people can hear me. This is the most important feature of a phone. Some companies have forgotten this basic imperative. I have not tried to do any fancy stuff, like 3-way calling or video voice mail yet.

2) The internal speaker works pretty well. I was able to listen to music, video, or online web video without any issues.

3) I like the way it organizes the SMS messages. Very ichat like… Hope they make this AIM/G-talk compatible soon.

4) The screen is incredible. I have never seen anything so sharp and clear in a hand-held device.