Thanks.

That shows us everything we need. After speaking to my sysadmins it  
seems that the problem is that one of those networks supports reverse  
name lookup whereas the other does not.

$ dig -x 137.205.125.113

; <<>> DiG 9.3.4-P1 <<>> -x 137.205.125.113
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 49639
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 10, ADDITIONAL: 8

;; QUESTION SECTION:
;113.125.205.137.in-addr.arpa.	IN	PTR

;; ANSWER SECTION:
113.125.205.137.in-addr.arpa. 69100 IN	PTR	scafell.astro.warwick.ac.uk.

;; AUTHORITY SECTION:
125.205.137.in-addr.arpa. 69100	IN	NS	zizi.chem.warwick.ac.uk.
125.205.137.in-addr.arpa. 69100	IN	NS	extdns1.warwick.ac.uk.
125.205.137.in-addr.arpa. 69100	IN	NS	extdns2.warwick.ac.uk.
125.205.137.in-addr.arpa. 69100	IN	NS	bar.csc.warwick.ac.uk.
125.205.137.in-addr.arpa. 69100	IN	NS	ns0.csc.warwick.ac.uk.
125.205.137.in-addr.arpa. 69100	IN	NS	ns1.csc.warwick.ac.uk.
125.205.137.in-addr.arpa. 69100	IN	NS	ns3.csc.warwick.ac.uk.
125.205.137.in-addr.arpa. 69100	IN	NS	dns0.warwick.ac.uk.
125.205.137.in-addr.arpa. 69100	IN	NS	dns1.warwick.ac.uk.
125.205.137.in-addr.arpa. 69100	IN	NS	dns2.warwick.ac.uk.

;; ADDITIONAL SECTION:
bar.csc.warwick.ac.uk.	84134	IN	A	137.205.124.91
ns0.csc.warwick.ac.uk.	84134	IN	A	137.205.124.88
ns1.csc.warwick.ac.uk.	84134	IN	A	137.205.124.89
ns3.csc.warwick.ac.uk.	84134	IN	A	137.205.124.80
dns0.warwick.ac.uk.	1334	IN	A	137.205.128.17
dns1.warwick.ac.uk.	1334	IN	A	137.205.128.18
dns2.warwick.ac.uk.	1334	IN	A	137.205.128.19
zizi.chem.warwick.ac.uk. 84134	IN	A	137.205.190.1

;; Query time: 6 msec
;; SERVER: 10.100.1.1#53(10.100.1.1)
;; WHEN: Wed Jul  1 10:56:43 2009
;; MSG SIZE  rcvd: 416

$ dig -x 137.205.62.131

; <<>> DiG 9.3.4-P1 <<>> -x 137.205.62.131
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 40374
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;131.62.205.137.in-addr.arpa.	IN	PTR

;; Query time: 1474 msec
;; SERVER: 10.100.1.1#53(10.100.1.1)
;; WHEN: Wed Jul  1 10:57:25 2009
;; MSG SIZE  rcvd: 45


We use tcp_wrappers on our firewall to filter out any packets that can  
not be traced back to an identifying origin. The git port was included  
in this.

We've turned the git tcp_wrappers off for the moment so you can verify  
that everything works now but we'd prefer it if your sysadmin can sort  
out the reverse name look up for your network.

Tim

On Jul 1, 2009, at 4:12 AM, Tom Marsh wrote:

> hi tim,
>
> traceroute shows no obvious difference whether I use it from my laptop
> (which does not work overall) or from my desktop which does:
>
> Here is an example from my laptop; see later for a run of 'nmap'
>
> /usr/sbin/traceroute starlink.jach.hawaii.edu -p 9418
> traceroute to starlink.jach.hawaii.edu (128.171.90.25), 30 hops max,  
> 40 byte
> packets using UDP
> 1  137.205.62.254 (137.205.62.254)  0.787 ms   0.761 ms   0.752 ms
>
> 2  campus-gw.warwick.ac.uk (137.205.1.14)  1.067 ms   1.287 ms    
> 0.976 ms
>
> 3  194.66.251.253 (194.66.251.253)  1.285 ms   2.310 ms   1.956 ms
>
> 4  193.63.208.33 (193.63.208.33)  1.691 ms   1.343 ms   1.435 ms
>
> 5  so-2-0-0.leed-sbr1.ja.net (146.97.42.73)  5.261 ms   5.154 ms    
> 5.435 ms
>
> 6  so-5-1-0.lond-sbr1.ja.net (146.97.33.98)  16.727 ms   16.851 ms    
> 12.756
> ms
> 7  so-5-0-0.lond-sbr3.ja.net (146.97.33.158)  10.303 ms   10.070 ms
> 10.980 ms
> 8  janet.rt1.lon.uk.geant2.net (62.40.124.197)  10.146 ms   10.240 ms
> 10.541 ms
> 9  so-2-0-0.rt1.ams.nl.geant2.net (62.40.112.137)  36.927 ms    
> 35.303 ms
> 32.671 ms
> 10  198.32.11.50 (198.32.11.50)  101.874 ms   114.509 ms   110.862 ms
> 11  so-0-0-0.0.rtr.wash.net.internet2.edu (64.57.28.11)  141.613 ms
> 136.993 ms   132.767 ms
> 12  so-0-0-0.0.rtr.atla.net.internet2.edu (64.57.28.6)  139.594 ms    
> 133.596
> ms   126.364 ms
> 13  so-3-2-0.0.rtr.hous.net.internet2.edu (64.57.28.43)  164.842 ms
> 156.815 ms   150.033 ms
> 14  so-3-0-0.0.rtr.losa.net.internet2.edu (64.57.28.44)  181.862 ms
> 181.594 ms   189.719 ms
> 15  aarnet-1-lo-jmb-702.lsanca.pacificwave.net (207.231.240.149)   
> 186.614 ms
>  183.312 ms   181.939 ms
> 16  ge-0-1-0.bb1.a.koa.aarnet.net.au (202.158.194.101)  229.126 ms    
> 229.036
> ms   229.184 ms
> 17  maunalani-aarnet.uhnet.net (205.166.205.254)  245.427 ms    
> 243.193 ms
> 236.001 ms
> 18  vlan244-hurp3750-maunalani.uhnet.net (205.166.205.246)  237.981 ms
> 233.799 ms   230.610 ms
> 19  128.171.73.33 (128.171.73.33)  249.835 ms   249.904 ms   249.841  
> ms
> 20  128.171.73.5 (128.171.73.5)  232.765 ms   232.142 ms   240.180 ms
> 21  * * *
> 22  * * *
> 23  * * *
> 24  * * *
> 25  * * *
> 26  * * *
> 27  * * *
> 28  * * *
> 29  * * *
> 30  * * *
>
> and here is nmap from my laptop:
>
> nmap -P0 -sT -p 80,9418 starlink.jach.hawaii.edu
>
> Starting Nmap 4.75 ( http://nmap.org ) at 2009-07-01 15:09 BST
> Interesting ports on ns1.jach.HAWAII.EDU (128.171.90.25):
> PORT     STATE SERVICE
> 80/tcp   open  http
> 9418/tcp open  unknown
>
> Nmap done: 1 IP address (1 host up) scanned in 0.30 seconds
>
> again, the same as my desktop, but I continue to get ' Connection  
> reset by
> peer'.
>
> inet address of my laptop:   137.205.62.131
> inet address of my desktop: 137.205.125.113
>
> tom

-- 
Tim Jenness
Joint Astronomy Centre