Error from log, after rebootDatabase Manager not working

Question

Ok, lets try this again :- )
I got Ubuntu 8.04, 32bit installed on a DL360 G3, I figured that I can learn how Oracle works, I don't want the Express Version, I need to learn what we will be using at work and not a limited edition.
After I re-boot the server I can't access what worked before, the Management URL:
https://dragonfly.mydomain.com:1158/em
so I type:
**raymond@dragonfly:/u01/app/oracle/diag/tnslsnr/dragonfly/listener/alert$ lsnrctl**
**LSNRCTL for Linux: Version 11.1.0.6.0 - Production on 07-OCT-2008 18:03:15**
**Copyright (c) 1991, 2007, Oracle. All rights reserved.**
**Welcome to LSNRCTL, type "help" for information.**
**LSNRCTL> status**
**Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1521)))**
**STATUS of the LISTENER**
**Alias LISTENER**
**Version TNSLSNR for Linux: Version 11.1.0.6.0 - Production**
**Start Date 06-OCT-2008 18:03:01**
**Uptime 1 days 0 hr. 0 min. 24 sec**
**Trace Level off**
**Security ON: Local OS Authentication**
**SNMP OFF**
**Listener Parameter File /u01/app/oracle/product/11.1.0/db_1/network/admin/listener.ora**
**Listener Log File /u01/app/oracle/diag/tnslsnr/dragonfly/listener/alert/log.xml**
**Listening Endpoints Summary...**
**(DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))**
**(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=dragonfly.mydomain.com)(PORT=1521)))**
**Services Summary...**
**Service "ORCLXDB.mydomain.com" has 1 instance(s).**
**Instance "ORCL", status READY, has 1 handler(s) for this service...**
**Service "orcl.mydomain.com" has 1 instance(s).**
**Instance "ORCL", status READY, has 1 handler(s) for this service...**
**Service "orcl_XPT.mydomain.com" has 1 instance(s).**
**Instance "ORCL", status READY, has 1 handler(s) for this service...**
**The command completed successfully**
**LSNRCTL>**
it lists port 1521 ? is that a different service, what is that ?
I tried
https://dragonfly.mydomain.com:1521/em ( I tried the direct ip address too )
error from browser is:
The connection to 192.168.1.105:1521 was interrupted while the page was loading.
The connection to dragonfly.mydomain.com:1521 was interrupted while the page was loading.
Interrupted, WTF ?
so I do the next logical step and look inside the log file, results are a repeating problem, same repeating entry:
*<msg time='2008-10-07T18:06:08.271-07:00' org_id='oracle' comp_id='tnslsnr'*
type='UNKNOWN' level='16' host_id='dragonfly'
host_addr='192.168.1.105'>
*<txt>07-OCT-2008 18:06:08 * 12502*
*</txt>*
*</msg>*
*<msg time='2008-10-07T18:06:08.272-07:00' org_id='oracle' comp_id='tnslsnr'*
type='UNKNOWN' level='16' host_id='dragonfly'
host_addr='192.168.1.105'>
*<txt>TNS-12502: TNS:listener received no CONNECT_DATA from client*
*</txt>*
*</msg>*
*<msg time='2008-10-07T18:06:08.273-07:00' org_id='oracle' comp_id='tnslsnr'*
type='UNKNOWN' level='16' host_id='dragonfly'
host_addr='192.168.1.105'>
*<txt>07-OCT-2008 18:06:08 * 12502*
*</txt>*
*</msg>*
*<msg time='2008-10-07T18:06:08.273-07:00' org_id='oracle' comp_id='tnslsnr'*
type='UNKNOWN' level='16' host_id='dragonfly'
host_addr='192.168.1.105'>
*<txt>TNS-12502: TNS:listener received no CONNECT_DATA from client*
*</txt>*
*</msg>*
*<msg time='2008-10-07T18:06:27.385-07:00' org_id='oracle' comp_id='tnslsnr'*
type='UNKNOWN' level='16' host_id='dragonfly'
host_addr='192.168.1.105'>
*<txt>07-OCT-2008 18:06:27 * 12502*
*</txt>*
*</msg>*
*<msg time='2008-10-07T18:06:27.385-07:00' org_id='oracle' comp_id='tnslsnr'*
type='UNKNOWN' level='16' host_id='dragonfly'
host_addr='192.168.1.105'>
*<txt>TNS-12502: TNS:listener received no CONNECT_DATA from client*
*</txt>*
*</msg>*
Some Help, what do these errors mean ? are they the root of my problem ?
I need to get this problem, fixed!! it's starting to bug me.

Answer 1

I stopped reading here: "I got Ubuntu 8.04"
Oracle is supported on many different flavors and versions of Linux: This isn't one of them.
If the point is to learn Oracle then learn Oracle in a fully supported configuration.
Now, instead of learning Oracle, you are leaning what happens when people ignore Oracle's advice and go off making a mess of things on their own.
If you use a supported configuration you can just follow the docs and it installs properly.
If the goal is to become an Ubuntu expert keep following the path you are on. If the point is to learn Oracle I'd suggest a course correction.