topic Re: RE: Telnet Issue in Operating System - HP-UX

RE: Telnet Issue

Henry Manda — Tue, 26 Apr 2011 05:41:05 GMT

Hi Guys,

I'm having a server communication problem.
The server is rx8640 running on HP-UX 11i v3, from the server, I can ping other machines on the network, I can also telnet them. But the server cannot be pinged or telneted from other machines.
Kindly assist.

Re: RE: Telnet Issue

Torsten. — Tue, 26 Apr 2011 05:44:08 GMT

Most likely the security settings prevent this, check with "bastille".

Re: RE: Telnet Issue

Henry Manda — Tue, 26 Apr 2011 06:08:13 GMT

Hi,

Bastille is not configured on the server, its also not a trusted system.i have configured the IP address, netmask and default gateway properly.From /etc/rc.config.d/netconf, telnet is enabled.

Re: RE: Telnet Issue

Ralph Grothe — Tue, 26 Apr 2011 07:50:37 GMT

Check if a listening socket is waiting for connections at port 23.

$ netstat -an|grep \\.23.*LISTEN
tcp 0 0 *.23 *.* LISTEN

AfaIk, in /etc/rc.config.d/netconf there's nothing to be configured regarding telnetd.
(at least on our 11iv1 hosts this is the case)

telnetd is usually started by inetd.
So check if it has a not commented out entry in inetd.conf.

$ grep ^[^#]*telnet /etc/inetd.conf
telnet stream tcp nowait root /usr/lbin/telnetd telnetd

If applicable remove the comment hashmark and let inetd reread its config by

# /usr/sbin/inetd -c

Re: RE: Telnet Issue

Henry Manda — Tue, 26 Apr 2011 09:11:43 GMT

Hi,

Telnet is enabled,
# netstat -an|grep \\.23.*LISTEN
tcp 0 0 *.2301 *.* LISTEN
tcp 0 0 *.23 *.* LISTEN
#
Again

I have also renoved the # on the telnetd line in the file /etc/inetd.conf,

The server cant even be pinged, but from it you can ping any machine on the net

Re: RE: Telnet Issue

Henry Manda — Tue, 26 Apr 2011 10:57:49 GMT

Guys,

Please assist me on this issue, Im really under pressure.what could be wrong?The server is not accepting any incoming connections, be it ping,telnet, ftp, etc.

Re: RE: Telnet Issue

Ralph Grothe — Tue, 26 Apr 2011 11:14:41 GMT

> The server cant even be pinged, but from it you can ping any machine on the net

Sorry Henry, I overread that the host cannot even be pinged.
How did you access it then? Via its console?
You don't happen to have any local packet filter running on this host?
Have you checked the state of the NIC(s) that should give you LAN connectivity?

e.g.

# netstat -in

Assuming it was NIC lan0, what state does an

# ifconfig lan0

show?
Has it initalized correctly?
Does

# lanadmin -sx 0

output correct mode an speed?
You can also look at its mibstats for accumulated errs and colls.

# lanadmin -g mibstats 0

Is your routing table correct?

# netstat -rn

Ask your network admin to have a look at the switch port settings (and for errs as well) where this NIC is connected to.

Re: RE: Telnet Issue

Henry Manda — Tue, 26 Apr 2011 12:11:28 GMT

Hi

I'm accessing the server via the console.
Below is the output of the commands you sent.
The network ports are working well even after exchanging with other servers.

#
#
#
# clear
# netstat -in
Name Mtu Network Address Ipkts Ierrs Opkts Oerrs Coll
lo0 32808 127.0.0.0 127.0.0.1 108138787 0 108139508 0 0
lan900 1500 192.168.0.0 192.168.0.50 4184950344 0 1459786174 0 0
# ifconfig lan900
lan900: flags=1843
inet 192.168.0.50 netmask ffffffc0 broadcast 192.168.0.63
#
#
# lanadmin -sx 0
Speed = 1000000000
Speed = 1000 Full-Duplex.
Autonegotiation = On.

# lanadmin -g mibstats 0

LAN INTERFACE STATUS DISPLAY
Tue , Apr 26,2011 16:09:39

PPA Number = 0
Description = lan0 HP PCI-X 1000Mbps Release B.11.31.0809
Type (value) = ethernet-csmacd(6)
MTU Size = 1500
Speed = 1000000000
Station Address = 0x17a4770004
Administration Status (value) = up(1)
Operation Status (value) = up(1)
Last Change = 135
Inbound Octets = 438630633
Inbound Unicast Packets = 1976572892
Inbound Non-Unicast Packets = 973746
Inbound Discards = 0
Inbound Errors = 0
Inbound Unknown Protocols = 142
Outbound Octets = 2192021612
Outbound Unicast Packets = 528836846
Outbound Non-Unicast Packets = 15787
Outbound Discards = 0
Outbound Errors = 0
Outbound Queue Length = 0
Specific = 655367

Ethernet-like Statistics Group

Index = 1
Alignment Errors = 0
FCS Errors = 0
Single Collision Frames = 0
Multiple Collision Frames = 0
Deferred Transmissions = 0
Late Collisions = 0
Excessive Collisions = 0
Internal MAC Transmit Errors = 0
Carrier Sense Errors = 0
Frames Too Long = 0
Internal MAC Receive Errors = 0

# netstat -rn
Routing tables
Destination Gateway Flags Refs Interface Pmtu
127.0.0.1 127.0.0.1 UH 0 lo0 32808
192.168.0.50 192.168.0.50 UH 0 lan900 32808
192.168.0.0 192.168.0.50 U 2 lan900 1500
127.0.0.0 127.0.0.1 U 0 lo0 32808
default 192.168.0.62 UG 0 lan900 1500
#

Re: RE: Telnet Issue

Noé — Tue, 26 Apr 2011 12:27:05 GMT

Hello.

Is this server behind a firewall?

Re: RE: Telnet Issue

Henry Manda — Tue, 26 Apr 2011 12:35:55 GMT

Ok, we have a firewall for our entire network. Other servers are on the same network and are not behaving the same.

Re: RE: Telnet Issue

Ralph Grothe — Tue, 26 Apr 2011 12:36:14 GMT

lan900 looks like an auto port aggregated NIC if I remember correctly.
I remember there was an hp_apa_util to do a few checks but I can't get hold of a box where we use the HP APA package.
Maybe if you look for some init script like /sbin/init.d/hp*apa* and try to restart it?
There isn't any connectivity now anyway, so it won't really hurt, albeit it might be futil either?

Re: RE: Telnet Issue

Laurent Menase — Tue, 26 Apr 2011 22:03:20 GMT

you should take network traces from the system , the peer system and the switch and router if there is one between the 2 systems.
try telnet in one way, try telnet in the other way
same with ping,
see where packet are disapearing in the trace

are you sure to don't have a duplicate ip?

Check arp data from the system, switch, routers,