------- Forwarded message -------
From: schutter <schutter@sunflower.com>
To: leeross@gci.net
Subject: can't ssh to system on ACS
Date: Sun, 02 Jul 2006 21:52:49 -0800
Lee:
Thanks for sending the emails with the message thread from AKLUG on making
network connections to systems on ACS. I could not gather any reason from
them, however, why ssh wouldn't be working to my sister's computer.
Hopefully someone at AKLUG, either Royce or someone else, may have some
ideas.
I will summarize the situation for the group. I live in Lawrence,
Kansas, and my sister lives in Anchorage. I have more technical knowledge
of computers than my sister and so I would like to be able to log into her
computer to help her with system administration type things. I have a
custom built system with an Asus A8V motherboard and Athlon64 3200+ cpu
running 64 bit SUSE Linux 9.3. My internet access is through my local
cable company, Sunflower Broadband. My system is connected to a standard
ethernet hub and then to a cable modem. My sister's computer is also a
custom built system with an A8V motherboard and Athlon64 3000+ cpu running
64 bit SUSE Linux 9.2. It is connected directly to an ACS DSL modem for
internet access.
When I try to ssh from my system to my sister's system I don't get any
response. As a test, I've tried some other things. Referring to the
network configuration data below for my sister's system, an instance of a
PPP conection can be seen with an IP address of 66.230.103.102 for the end
on my sister's computer and an IP address of 66.230.103.254 for the ISP
end. In this case, I can ping and traceroute to 66.230.103.254 just
fine. However, if I ping 66.230.103.102 I don't get any response and if I
traceroute to the same address, I get a couple of levels into ACS's
routers and then the traceroute dies. Doing an ssh to 66.230.103.254 also
gets no response. I had my sister call ACS tech support and ask them if
ACS blocked port 22 and they said they did not. Lee Ross has also
forwarded to me some messages from the AKLUG mailing list which state that
ACS does not block port 22. However, I decided to try some tests with an
arbitrary port just to be thorough. I made a random choice of port 1004.
Lee configured the SSH server on my sister's computer to listen on that
port. When I did an ssh to her computer using port 1004 I still got no
response. Doing an ssh to 66.230.103.254 using port 1004, however, yeilds
an "access denied" response. Also of interest, I had Lee try an ssh from
my sister's computer to my computer, and it worked fine.
I notice that SUSE does not list a default route in the output of netstat,
which seems unusual. However, the use of the 0.0.0.0 network address
apparently takes care of this. The "ifstatus eth0" command does list
"default via 24.124.91.254" on my system. This brings me to my final
point, which is that the "ifstatus eth0" command on my sister's computer
states "dhcpcd is still waiting for data", and does not list any active
routes. I've had my sister send me the network info from her computer on
several different occasions (I sent her a script to run) and eth0 always
appears this way. So it seems normal for her system, although still
possibly not correct. The network configuration does work, at least for
locally initiated connections. However, could the SUSE DHCP client not be
working properly with the ACS DHCP server? Or is this just a quirk of DSL?
I don't have any direct experience with DSL so I'm pretty much in the dark
here. Any insight or suggestions would be much appreciated. The network
configuration for my sister's system (hostname "linux") and my system
(hostname "faye") follows.
Thanks,
John Schutter
Network info for my sister's system ("linux"):
/etc/hosts
**********
#
# hosts This file describes a number of hostname-to-address
# mappings for the TCP/IP subsystem. It is mostly
# used at boot time, when no name servers are running.
# On small systems, this file can be used instead of a
# "named" name server.
# Syntax:
#
# IP-Address Full-Qualified-Hostname Short-Hostname
#
127.0.0.1 localhost
# special IPv6 addresses
::1 localhost ipv6-localhost ipv6-loopback
fe00::0 ipv6-localnet
ff00::0 ipv6-mcastprefix
ff02::1 ipv6-allnodes
ff02::2 ipv6-allrouters
ff02::3 ipv6-allhosts
127.0.0.2 linux.acsalaska.net linux
_____________
# netstat -in
*************
Kernel Interface table
Iface MTU Met RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR
Flg
dsl0 1492 0 62 0 0 0 72 0 0 0
MOPRU
eth0 1500 0 565 0 0 0 90 0 0 0
BMNRU
lo 16436 0 50 0 0 0 50 0 0 0
LRU
_____________
# netstat -rn
*************
Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt
Iface
66.230.103.254 0.0.0.0 255.255.255.255 UH 0 0 0
dsl0
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
0.0.0.0 66.230.103.254 0.0.0.0 UG 0 0 0
dsl0
_______________
# ifconfig
***************
dsl0 Link encap:Point-to-Point Protocol
inet addr:66.230.103.102 P-t-P:66.230.103.254
Mask:255.255.255.255
UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1492 Metric:1
RX packets:62 errors:0 dropped:0 overruns:0 frame:0
TX packets:72 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:3
RX bytes:7186 (7.0 Kb) TX bytes:3822 (3.7 Kb)
eth0 Link encap:Ethernet HWaddr 00:48:54:65:40:C2
inet6 addr: fe80::248:54ff:fe65:40c2/64 Scope:Link
UP BROADCAST NOTRAILERS RUNNING MULTICAST MTU:1500 Metric:1
RX packets:565 errors:0 dropped:0 overruns:0 frame:0
TX packets:90 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:84978 (82.9 Kb) TX bytes:11829 (11.5 Kb)
Interrupt:169 Base address:0xe000
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:50 errors:0 dropped:0 overruns:0 frame:0
TX packets:50 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:3260 (3.1 Kb) TX bytes:3260 (3.1 Kb)
_______________
# ifstatus eth0
***************
eth0 device: Realtek Semiconductor Co., Ltd.
RTL-8139/8139C/8139C+ (rev 10)
eth0 configuration: eth-id-00:48:54:65:40:c2
eth0 dhcpcd is still waiting for data
eth0 is up
2: eth0: <BROADCAST,MULTICAST,NOTRAILERS,UP> mtu 1500 qdisc pfifo_fast
qlen 1000
link/ether 00:48:54:65:40:c2 brd ff:ff:ff:ff:ff:ff
inet6 fe80::248:54ff:fe65:40c2/64 scope link
valid_lft forever preferred_lft forever
Configured routes for interface eth0:
169.254.0.0 - 255.255.0.0 eth0
0 of 1 configured routes for interface eth0 up
_______________
# ifstatus dsl0
***************
dsl0
interface dsl0 is up
_______________
Network info for my system ("faye"):
/etc/hosts
**********
#
# hosts This file describes a number of hostname-to-address
# mappings for the TCP/IP subsystem. It is mostly
# used at boot time, when no name servers are running.
# On small systems, this file can be used instead of a
# "named" name server.
# Syntax:
#
# IP-Address Full-Qualified-Hostname Short-Hostname
#
127.0.0.1 localhost
# special IPv6 addresses
::1 localhost ipv6-localhost ipv6-loopback
fe00::0 ipv6-localnet
ff00::0 ipv6-mcastprefix
ff02::1 ipv6-allnodes
ff02::2 ipv6-allrouters
ff02::3 ipv6-allhosts
127.0.0.2 faye.lawrence.ks.us faye
_____________
# netstat -in
*************
Kernel Interface table
Iface MTU Met RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR
Flg
eth0 1500 0 766416 0 0 0 19 0 0 0
BMNRU
lo 16436 0 11752 0 0 0 11752 0 0 0
LRU
_____________
# netstat -rn
*************
Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt
Iface
24.124.88.0 0.0.0.0 255.255.252.0 U 0 0 0
eth0
169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0
eth0
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
0.0.0.0 24.124.91.254 0.0.0.0 UG 0 0 0
eth0
_______________
# ifconfig
***************
eth0 Link encap:Ethernet HWaddr 00:13:D4:21:76:E9
inet addr:24.124.90.235 Bcast:24.124.91.255 Mask:255.255.252.0
inet6 addr: fe80::213:d4ff:fe21:76e9/64 Scope:Link
UP BROADCAST NOTRAILERS RUNNING MULTICAST MTU:1500 Metric:1
RX packets:766416 errors:0 dropped:0 overruns:0 frame:0
TX packets:19 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:538104381 (513.1 Mb) TX bytes:2224 (2.1 Kb)
Interrupt:201 Memory:f9c00000-0
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:11752 errors:0 dropped:0 overruns:0 frame:0
TX packets:11752 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:1729726 (1.6 Mb) TX bytes:1729726 (1.6 Mb)
_______________
# ifstatus eth0
***************
eth0 device: Marvell Technology Group Ltd. Gigabit Ethernet
Controller (rev 13)
eth0 configuration: eth-id-00:13:d4:21:76:e9
eth0 DHCP client (dhcpcd) is running
IPADDR=24.124.90.235
NETMASK=255.255.252.0
GATEWAY=24.124.91.254
DOMAIN='lawrence.ks.us'
DNS=24.124.0.193,24.124.0.194,24.124.0.1
DHCPSIADDR=24.124.0.253
DHCPCHADDR=00:13:D4:21:76:E9
REBINDTIME=9450
eth0 is up
3: eth0: <BROADCAST,MULTICAST,NOTRAILERS,UP> mtu 1500 qdisc pfifo_fast
qlen 1000
link/ether 00:13:d4:21:76:e9 brd ff:ff:ff:ff:ff:ff
inet 24.124.90.235/22 brd 24.124.91.255 scope global eth0
inet6 fe80::213:d4ff:fe21:76e9/64 scope link
valid_lft forever preferred_lft forever
eth0 IP address: 24.124.90.235/22
Configured routes for interface eth0:
169.254.0.0 - 255.255.0.0 eth0
Active routes for interface eth0:
24.124.88.0/22 proto kernel scope link src 24.124.90.235
169.254.0.0/16 scope link
default via 24.124.91.254
1 of 1 configured routes for interface eth0 up
_______________
-- Lee Ross Anchorage, AK --------- To unsubscribe, send email to <aklug-request@aklug.org> with 'unsubscribe' in the message body.Received on Mon Jul 3 09:03:13 2006
This archive was generated by hypermail 2.1.8 : Mon Jul 03 2006 - 09:03:13 AKDT