Network computer name problem w/ Tiger and DRb

ruby-talk
1

Hi

While running DRb, I noticed that a timeout was occuring with the URI
provided by DRb.uri. On my powerbook, DRb returned as the URI:

   druby://<computer_name>.local:port

Executing the first remote call within DRb took over a minute on
my powerbook, but was instantaneous on my sun box.

When I changed <computer_name> to <ip.ad.re.ss>, the delay
issue disappeared.

Thinking it may be a configuration issue, I fiddled with

  Socket.do_not_reverse_lookup = true

but did not had any luck.

This is disconcerting since I had hoped that DRb.uri would return a
good address.

Does anyone know what the problem is here?

Thanks

···

--
Jim Freeze

2

While running DRb, I noticed that a timeout was occuring with the URI
provided by DRb.uri. On my powerbook, DRb returned as the URI:

   druby://<computer_name>.local:port

Executing the first remote call within DRb took over a minute on
my powerbook, but was instantaneous on my sun box.

Sounds like your DNS is not completely configured.

When I changed <computer_name> to <ip.ad.re.ss>, the delay
issue disappeared.

This is disconcerting since I had hoped that DRb.uri would return a
good address.

Does anyone know what the problem is here?

From the sun, what does `host ip.ad.re.ss` (or dig or nslookup) where ip.ad.re.ss is the address of the powerbook return?

If you don't have matching forward and reverse DNS, DRb won't be able to return a good hostname.

···

On Nov 10, 2005, at 2:38 PM, Jim Freeze wrote:

--
Eric Hodel - drbrain@segment7.net - http://segment7.net
FEC2 57F1 D465 EB15 5D6E 7C11 332A 551C 796C 9F04

3

This sounds like a simple DNS lookup issue with computer_name.

That'd be the first place I would investigate, anyway.

Kirk Haines

···

On Thursday 10 November 2005 3:38 pm, Jim Freeze wrote:

When I changed <computer_name> to <ip.ad.re.ss>, the delay
issue disappeared.

Thinking it may be a configuration issue, I fiddled with

  Socket.do_not_reverse_lookup = true

4

I also found some weird stuff with DRb & uri..

In specific, the receiving server would not yield data to the client
if the clients primary dns suffix was not dns-able.... In my opinion,
I would htink the server would attempt to validate or dns the client
via wins or lm/hosts but.. dunno..

My article here:
http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-talk/157389?help-en

good luck

···

On 11/10/05, Jim Freeze <jim@freeze.org> wrote:

Hi

While running DRb, I noticed that a timeout was occuring with the URI
provided by DRb.uri. On my powerbook, DRb returned as the URI:

   druby://<computer_name>.local:port

Executing the first remote call within DRb took over a minute on
my powerbook, but was instantaneous on my sun box.

When I changed <computer_name> to <ip.ad.re.ss>, the delay
issue disappeared.

Thinking it may be a configuration issue, I fiddled with

  Socket.do_not_reverse_lookup = true

but did not had any luck.

This is disconcerting since I had hoped that DRb.uri would return a
good address.

Does anyone know what the problem is here?

Thanks

--
Jim Freeze

5

> While running DRb, I noticed that a timeout was occuring with the URI
> provided by DRb.uri. On my powerbook, DRb returned as the URI:
>
> druby://<computer_name>.local:port
>
> Executing the first remote call within DRb took over a minute on
> my powerbook, but was instantaneous on my sun box.

Sounds like your DNS is not completely configured.

The PowerBook DNS? BTW, I am attaching to my company network.

From the sun, what does `host ip.ad.re.ss` (or dig or nslookup)
where ip.ad.re.ss is the address of the powerbook return?

It says:

% host /jim-freezes-powerbook-g4-15.local
Host /jim-freezes-powerbook-g4-15.local not found: 3(NXDOMAIN)

But DRb still works, it just has to wait for a timeout for the first
remote call.
All subsequent calls are fast.

If you don't have matching forward and reverse DNS, DRb won't be able
to return a good hostname.

Since the computer connects with DHCP to the network, adding host entry
won't help here. And, I don't think I should have to run bind on my
laptop to get this to work.

Any suggestions?

···

On 11/10/05, Eric Hodel <drbrain@segment7.net> wrote:

On Nov 10, 2005, at 2:38 PM, Jim Freeze wrote:

--
Jim Freeze

6

BTW, host failed, but dig seems to work:

% dig 'jim-freezes-powerbook-g4-15.local'

; <<>> DiG 9.2.2 <<>> jim-freezes-powerbook-g4-15.local
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 50543
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0

;; QUESTION SECTION:
;jim-freezes-powerbook-g4-15.local. IN A

;; AUTHORITY SECTION:
. 539 IN SOA frootb.mycompany.net.
dnssupport.mycompany.com. 2004059055 14400 3600 604800 600

;; Query time: 66 msec
;; SERVER: 10.208.0.3#53(10.208.0.3)
;; WHEN: Thu Nov 10 17:00:07 2005
;; MSG SIZE rcvd: 130

···

--
Jim Freeze

7

While running DRb, I noticed that a timeout was occuring with the URI
provided by DRb.uri. On my powerbook, DRb returned as the URI:

   druby://<computer_name>.local:port

Executing the first remote call within DRb took over a minute on
my powerbook, but was instantaneous on my sun box.

Sounds like your DNS is not completely configured.

The PowerBook DNS? BTW, I am attaching to my company network.

From the sun, what does `host ip.ad.re.ss` (or dig or nslookup)
where ip.ad.re.ss is the address of the powerbook return?

It says:

% host /jim-freezes-powerbook-g4-15.local
Host /jim-freezes-powerbook-g4-15.local not found: 3(NXDOMAIN)

A failure with your IP address is more informative. I wouldn't expect every DHCP server to properly update DNS when it hands out leases.

But DRb still works, it just has to wait for a timeout for the first
remote call.
All subsequent calls are fast.

Right, DRb does an RDNS lookup to figure out the local host name, which probably takes forever.

If you don't have matching forward and reverse DNS, DRb won't be able
to return a good hostname.

Since the computer connects with DHCP to the network, adding host entry
won't help here. And, I don't think I should have to run bind on my
laptop to get this to work.

Any suggestions?

The DHCP address you're handed should have matching forward and reverse DNS. Complain to your network admins.

···

On Nov 10, 2005, at 2:59 PM, Jim Freeze wrote:

On 11/10/05, Eric Hodel <drbrain@segment7.net> wrote:

On Nov 10, 2005, at 2:38 PM, Jim Freeze wrote:

--
Eric Hodel - drbrain@segment7.net - http://segment7.net
FEC2 57F1 D465 EB15 5D6E 7C11 332A 551C 796C 9F04

8

> If you don't have matching forward and reverse DNS, DRb won't be able
> to return a good hostname.

Since the computer connects with DHCP to the network, adding host entry
won't help here. And, I don't think I should have to run bind on my
laptop to get this to work.

Not on your laptop. But your DHCP server and you DNS server should
probably talk to each other so that:

1) your laptop gets a meaningful domain name (I doubt 'local' is it)
2) have the DNS server know about the IP given away by the DHCP server.

If you are using dhcpd by isc.org, lookup the 'DYNAMIC DNS UPDATES'
paragraph in the dhcpd.conf(5) man page.

Guillaume.

···

On Fri, 2005-11-11 at 07:59 +0900, Jim Freeze wrote:

Any suggestions?
--
Jim Freeze

9

BTW, host failed, but dig seems to work:

No, this dig output shows that there is no answers to your query. So the
look up failed.

% dig 'jim-freezes-powerbook-g4-15.local'

; <<>> DiG 9.2.2 <<>> jim-freezes-powerbook-g4-15.local
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 50543
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0

                      ^^^^^^^^^^^^^^^^^^^

;; QUESTION SECTION:
;jim-freezes-powerbook-g4-15.local. IN A

This is your question/query.

No ANSWER SECTION.

HTH,
Guillaume.

···

On Fri, 2005-11-11 at 08:01 +0900, Jim Freeze wrote:

;; AUTHORITY SECTION:
. 539 IN SOA frootb.mycompany.net.
dnssupport.mycompany.com. 2004059055 14400 3600 604800 600

;; Query time: 66 msec
;; SERVER: 10.208.0.3#53(10.208.0.3)
;; WHEN: Thu Nov 10 17:00:07 2005
;; MSG SIZE rcvd: 130

--
Jim Freeze

10

BTW, host failed, but dig seems to work:

% dig 'jim-freezes-powerbook-g4-15.local'

; <<>> DiG 9.2.2 <<>> jim-freezes-powerbook-g4-15.local
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 50543
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0

                                 ^^^^^^^^^

ANSWER would be 1 if it found a matching record.

···

On Nov 10, 2005, at 3:01 PM, Jim Freeze wrote:

;; QUESTION SECTION:
;jim-freezes-powerbook-g4-15.local. IN A

;; AUTHORITY SECTION:
. 539 IN SOA frootb.mycompany.net.
dnssupport.mycompany.com. 2004059055 14400 3600 604800 600

;; Query time: 66 msec
;; SERVER: 10.208.0.3#53(10.208.0.3)
;; WHEN: Thu Nov 10 17:00:07 2005
;; MSG SIZE rcvd: 130

--
Jim Freeze

--
Eric Hodel - drbrain@segment7.net - http://segment7.net
FEC2 57F1 D465 EB15 5D6E 7C11 332A 551C 796C 9F04

11

> But DRb still works, it just has to wait for a timeout for the first
> remote call.
> All subsequent calls are fast.

Right, DRb does an RDNS lookup to figure out the local host name,
which probably takes forever.

What is RDNS. Is there a command line version of this so I can
see it work?

> Any suggestions?

The DHCP address you're handed should have matching forward and
reverse DNS. Complain to your network admins.

Yes. I will. Is there a commandline app that will show that a matching
reverse DNS is not being provided? Or just a dig failure?

···

On 11/10/05, Eric Hodel <drbrain@segment7.net> wrote:

--
Jim Freeze

12

Jim Freeze <jim@freeze.org> writes:

> But DRb still works, it just has to wait for a timeout for the first
> remote call.
> All subsequent calls are fast.

Right, DRb does an RDNS lookup to figure out the local host name,
which probably takes forever.

What is RDNS. Is there a command line version of this so I can
see it work?

reverse dns.

$ dig -x 68.142.226.47

; <<>> DiG 9.2.4 <<>> -x 68.142.226.47
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 943
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

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

;; ANSWER SECTION:
47.226.142.68.in-addr.arpa. 1200 IN PTR p16.www.re2.yahoo.com.

;; Query time: 154 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Thu Nov 10 19:39:59 2005
;; MSG SIZE rcvd: 79

$ dig p16.www.re2.yahoo.com.

; <<>> DiG 9.2.4 <<>> p16.www.re2.yahoo.com.
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 50006
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;p16.www.re2.yahoo.com. IN A

;; ANSWER SECTION:
p16.www.re2.yahoo.com. 1800 IN A 68.142.226.47

;; Query time: 158 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Thu Nov 10 19:40:07 2005
;; MSG SIZE rcvd: 55

YS

···

On 11/10/05, Eric Hodel <drbrain@segment7.net> wrote:

13

But DRb still works, it just has to wait for a timeout for the first
remote call.
All subsequent calls are fast.

Right, DRb does an RDNS lookup to figure out the local host name,
which probably takes forever.

What is RDNS. Is there a command line version of this so I can
see it work?

Reverse DNS. You do a RDNS lookup when you look up by IP instead of by name:

$ ifconfig fxp0 | grep inet
         inet 192.168.1.13 netmask 0xffffff00 broadcast 192.168.1.255
         inet6 fe80::208:2ff:febb:cd4c%fxp0 prefixlen 64 scopeid 0x1

Reverse:

$ host 192.168.1.13
13.1.168.192.in-addr.arpa domain name pointer RUR-3.coop.robotcoop.com.

Forward:

$ host rur-3.coop.robotcoop.com
rur-3.coop.robotcoop.com has address 192.168.1.13

Any suggestions?

The DHCP address you're handed should have matching forward and
reverse DNS. Complain to your network admins.

Yes. I will. Is there a commandline app that will show that a matching
reverse DNS is not being provided? Or just a dig failure?

$ host `ifconfig | grep 'inet ' | grep -v '127' | cut -d ' ' -f 2`
70.1.168.192.in-addr.arpa domain name pointer kaa.coop.robotcoop.com.

Should do it for BSDlike systems like your Mac.

···

On Nov 10, 2005, at 3:29 PM, Jim Freeze wrote:

On 11/10/05, Eric Hodel <drbrain@segment7.net> wrote:

--
Eric Hodel - drbrain@segment7.net - http://segment7.net
FEC2 57F1 D465 EB15 5D6E 7C11 332A 551C 796C 9F04

14

Thanks for all the good info, but I am still confused as to how
drb client utlimately got the ip address of the server machine when
it is impossible to do from the commandline.

···

On 11/10/05, Eric Hodel <drbrain@segment7.net> wrote:

On Nov 10, 2005, at 3:29 PM, Jim Freeze wrote:
$ host `ifconfig | grep 'inet ' | grep -v '127' | cut -d ' ' -f 2`
70.1.168.192.in-addr.arpa domain name pointer kaa.coop.robotcoop.com.

--
Jim Freeze

15

Netbios? Can you ping the hostname?

···

On 11/10/05, Jim Freeze <jim@freeze.org> wrote:

On 11/10/05, Eric Hodel <drbrain@segment7.net> wrote:
> On Nov 10, 2005, at 3:29 PM, Jim Freeze wrote:
> $ host `ifconfig | grep 'inet ' | grep -v '127' | cut -d ' ' -f 2`
> 70.1.168.192.in-addr.arpa domain name pointer kaa.coop.robotcoop.com.

Thanks for all the good info, but I am still confused as to how
drb client utlimately got the ip address of the server machine when
it is impossible to do from the commandline.

--
Jim Freeze

16

I don't have a clear-enough picture of your environment to answer this for you.

I'd need to know which machine is the server, which is the client, the forward and reverse DNS for each machine, and an output of the failure.

···

On Nov 10, 2005, at 6:30 PM, Jim Freeze wrote:

On 11/10/05, Eric Hodel <drbrain@segment7.net> wrote:

On Nov 10, 2005, at 3:29 PM, Jim Freeze wrote:
$ host `ifconfig | grep 'inet ' | grep -v '127' | cut -d ' ' -f 2`
70.1.168.192.in-addr.arpa domain name pointer kaa.coop.robotcoop.com.

Thanks for all the good info, but I am still confused as to how
drb client utlimately got the ip address of the server machine when
it is impossible to do from the commandline.

--
Eric Hodel - drbrain@segment7.net - http://segment7.net
FEC2 57F1 D465 EB15 5D6E 7C11 332A 551C 796C 9F04

17

# From Sun box
% ping JDFPBook
ping: unknown host JDFPBook

# From PowerBook
% ping JDFPBook
ping: cannot resolve JDFPBook: Unknown host

···

On 11/10/05, x1 <caldridge@gmail.com> wrote:

Netbios? Can you ping the hostname?

--
Jim Freeze

18

Tell me the IP & submet mask of both machines..

my guess is that they're not in the same subnet...

···

On 11/11/05, Eric Hodel <drbrain@segment7.net> wrote:

On Nov 10, 2005, at 6:30 PM, Jim Freeze wrote:

> On 11/10/05, Eric Hodel <drbrain@segment7.net> wrote:
>> On Nov 10, 2005, at 3:29 PM, Jim Freeze wrote:
>> $ host `ifconfig | grep 'inet ' | grep -v '127' | cut -d ' ' -f 2`
>> 70.1.168.192.in-addr.arpa domain name pointer kaa.coop.robotcoop.com.
>
> Thanks for all the good info, but I am still confused as to how
> drb client utlimately got the ip address of the server machine when
> it is impossible to do from the commandline.

I don't have a clear-enough picture of your environment to answer
this for you.

I'd need to know which machine is the server, which is the client,
the forward and reverse DNS for each machine, and an output of the
failure.

--
Eric Hodel - drbrain@segment7.net - http://segment7.net
FEC2 57F1 D465 EB15 5D6E 7C11 332A 551C 796C 9F04