RSS feed valid but twitterfeed reports cannot parse

I've taken a closer look, and there's something very strange going on.. re-running the parsing manually from the machine that runs the feed processing, it sometimes works and sometimes doesn't (that's without changing any code anywhere), so it's definitely not an issue with the feed content itself, but there's something else that sometimes stops the feed from being parsed. I'll try and dig a little deeper to see if there's anything I can find that may cause this. ( Delete or Edit)

It appears to be a DNS issue of some sort, I'm getting "Error: 500 Can't connect to feeds.gizmodo.com.au:80 (Bad hostname 'feeds.gizmodo.com.au')" about half the time when making manual requests, while it works the other half of the time.

I'll check with my hosting provider to see if they are aware of any issues. ( Delete or Edit)

It actually looks like it may be a DNS issue with the nameservers of these 2 domains (both gizmodo.com.au and lifehacker.com.au use the same nameservers) - 2 respond with warnings - 1 doesn't respond at all:

alex@alex:~$ dig feeds.gizmodo.com.au @ns1.yourdnshost.net
;; Warning: Message parser reports malformed message packet.
;; Truncated, retrying in TCP mode.

; <<>> DiG 9.5.1-P2 <<>> feeds.gizmodo.com.au @ns1.yourdnshost.net
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 104
;; flags: qr rd; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0
;; WARNING: recursion requested but not available

;; QUESTION SECTION:
;feeds.gizmodo.com.au. IN A

;; ANSWER SECTION:
feeds.gizmodo.com.au. 3600 IN CNAME
sitesalluremediacomau.feedproxy.ghs.google.com.

;; Query time: 595 msec
;; SERVER: 202.124.241.10#53(202.124.241.10)
;; WHEN: Fri May 29 11:40:15 2009
;; MSG SIZE rcvd: 98

alex@alex:~$ dig feeds.gizmodo.com.au @ns2.yourdnshost.net
;; Warning: Message parser reports malformed message packet.
;; Truncated, retrying in TCP mode.

; <<>> DiG 9.5.1-P2 <<>> feeds.gizmodo.com.au @ns2.yourdnshost.net
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 30541
;; flags: qr rd; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0
;; WARNING: recursion requested but not available

;; QUESTION SECTION:
;feeds.gizmodo.com.au. IN A

;; ANSWER SECTION:
feeds.gizmodo.com.au. 3600 IN CNAME
sitesalluremediacomau.feedproxy.ghs.google.com.

;; Query time: 594 msec
;; SERVER: 202.124.241.100#53(202.124.241.100)
;; WHEN: Fri May 29 11:40:20 2009
;; MSG SIZE rcvd: 98

alex@alex:~$ dig feeds.gizmodo.com.au @ns3.yourdnshost.net

; <<>> DiG 9.5.1-P2 <<>> feeds.gizmodo.com.au @ns3.yourdnshost.net
;; global options: printcmd
;; connection timed out; no servers could be reached ( Delete or Edit)

Intermittent problems with Pipes are more likely related to this: http://getsatisfaction.com/twitterfee... ( Delete or Edit)

There was a problem with the "test feed" functionality which should now be fixed, not sure if this is related. If it still doesn't work, can you let me know the feed URL(s) which can't be parsed and I'll try and take a look. ( Delete or Edit)

This feed seems to be valid and parses ok, but I can't see it in the database. There was a problem with the "test feed" functionality which should now be fixed, not sure if this is related. ( Delete or Edit)

This feed now shows "ok", so it's likely a temporary issues. Sometimes requests can time our or take too long for twitterfeed to receive the feed content, resulting in these errors, but these are typically network-related and not permanent. ( Delete or Edit)

The problem is exactly that you need to be signed in to see the feed. When twitterfeed requests this feed URL, it gets redirected to this "you must be signed in" web page, which is obviously not a valid feed, so that's why it complains. Currently twitterfeed only support feeds that don't require authentication I'm afraid. ( Delete or Edit)

Strange - feedvalidator does show an issue, but I don't think that's the reason (http://feedvalidator.org/check.cgi?ur...), although of course it won't hurt to fix it just in case.

Other than that, what I noticed is that the first time I tried to parse the feed it failed, but after that it worked ok. Is it possible that the feed is cached for a time, so when it's fetched the first time after some interval it does some processing (perhaps leading to our request timing out?), but on subsequent fetches it works because it quickly serves a cached page?

This is all just theory, but it seems strange that the only time I managed to reproduce the error was the first time I tried.. ( Delete or Edit)

Hmm... you see, that's the odd thing, the second request works, but the first one never does. So when you test the feed yourself in twitterfeed, the first time it seems to fail, but the second time it works. This does seem to suggest that it returns something else the first time. The problem is that when processing the feed, it will only check it once, so that's probably why it fails.
We're in the process of rolling out a new back-end, so for now I have moved your feed to the new backend in the hope that this will work differently (but will have to wait and see, not sure right now if it makes a difference). ( Delete or Edit)

This is almost certainly related to a problem that Yahoo! Pipes seem to have at the moment, see http://getsatisfaction.com/twitterfee... ( Delete or Edit)