RE: telnet into a netgear switch?

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------------------------------
Message: 2
Date: Sun, 24 Nov 2013 18:47:09 -0800
From: David Birdsong <david@imgix.com>
To: nanog@nanog.org
Subject: telnet into a netgear switch?
Message-ID:
        <CAOMvUQfeM_Wnc=

eS1vz0Gh_pp-vZ+sPRk9Td-1U0A34c3A6jdQ@mail.gmail.com>

Content-Type: text/plain; charset=ISO-8859-1

Hey all, last night while at the datacenter I was in a pinch to extend a
rack's LAN. I compromised and ran out to the local Fry's to buy whatever
switch I could find so as to allow some configuration to happen while
we wait for the real network gear to show up.

I left before confirming I could access the switch remotely; it was very
late and I was pretty groggy and hey, any network gear has to be
telnet'table this day and age. Of course I was mostly wrong.

The switch expects some signed payload before allowing a telnet through. I
found this: https://code.google.com/p/netgear-telnetenable/...but I'm
having a hell of a time getting anything to respond.

The most confounding part is the switch doesn't respond to a single SYN
packet on low ports. I'm scanning all the ports now, but if nothing shows
up, I'm not sure what a payload is good for if the switch doesn't ACK a
single SYN.

I'm curious if anybody's got any tips besides not using Netgear in the
datacenter.

I have the MAC, I've IP'd it via DHCP, and the model number: JGS524E and I
can power cycle the switch as much as needed.

P.S. long time listener, first time caller. i'm more of a sysadmin
dangerously standing in for a proper network person.
------------------------------

Seems to me that you need to use their "Switch Configuration Utility" to
manage the switch. I didn't read all the documentation, but that is what
jumps out at me after a brief look. Maybe it will allow you to enable
telnet or ssh from there. See the following link:

No windows box handy, nor the desire for that hoop.

...but what magic is a windows app going to perform to wake up an
unresponsive TCP stack?

3

It could be any number of things, APC for example need a vendor option set
in DHCP or a ³Magic² ping. It could be that the app just talks to it on L2
like Microtik¹s. I suspect the windows app will be your only option.

4

>
> ------------------------------
> Message: 2
> Date: Sun, 24 Nov 2013 18:47:09 -0800
> From: David Birdsong <david@imgix.com>
> To: nanog@nanog.org
> Subject: telnet into a netgear switch?
> Message-ID:
> <CAOMvUQfeM_Wnc=
eS1vz0Gh_pp-vZ+sPRk9Td-1U0A34c3A6jdQ@mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
>
> Hey all, last night while at the datacenter I was in a pinch to extend a
> rack's LAN. I compromised and ran out to the local Fry's to buy whatever
> switch I could find so as to allow some configuration to happen while
> we wait for the real network gear to show up.
>
> I left before confirming I could access the switch remotely; it was very
> late and I was pretty groggy and hey, any network gear has to be
> telnet'table this day and age. Of course I was mostly wrong.
>
> The switch expects some signed payload before allowing a telnet through.
I
> found this: https://code.google.com/p/netgear-telnetenable/...but I'm
> having a hell of a time getting anything to respond.
>
> The most confounding part is the switch doesn't respond to a single SYN
> packet on low ports. I'm scanning all the ports now, but if nothing shows
> up, I'm not sure what a payload is good for if the switch doesn't ACK a
> single SYN.
>
> I'm curious if anybody's got any tips besides not using Netgear in the
> datacenter.
>
> I have the MAC, I've IP'd it via DHCP, and the model number: JGS524E and
I
> can power cycle the switch as much as needed.
>
>
> P.S. long time listener, first time caller. i'm more of a sysadmin
> dangerously standing in for a proper network person.
> ------------------------------
>
> Seems to me that you need to use their "Switch Configuration Utility" to
> manage the switch. I didn't read all the documentation, but that is what
> jumps out at me after a brief look. Maybe it will allow you to enable
> telnet or ssh from there. See the following link:
>

No windows box handy, nor the desire for that hoop.

...but what magic is a windows app going to perform to wake up an
unresponsive TCP stack?

In view that the application needs to be run directly on the LAN, I'm not
sure why you'd expect any TCP/IP like protocol - I asked a friend for a
packet capture and it seems that the configuration utility is using RRCP (
http://en.wikipedia.org/wiki/Realtek_Remote_Control_Protocol).

HTH

5

Ahh; I don't use windows either, but I keep a VM handy just in case I need
it.

jp

6

>
> ------------------------------
> Message: 2
> Date: Sun, 24 Nov 2013 18:47:09 -0800
> From: David Birdsong <david@imgix.com>
> To: nanog@nanog.org
> Subject: telnet into a netgear switch?
> Message-ID:
> <CAOMvUQfeM_Wnc=
eS1vz0Gh_pp-vZ+sPRk9Td-1U0A34c3A6jdQ@mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
>
> Hey all, last night while at the datacenter I was in a pinch to extend a
> rack's LAN. I compromised and ran out to the local Fry's to buy whatever
> switch I could find so as to allow some configuration to happen while
> we wait for the real network gear to show up.
>
> I left before confirming I could access the switch remotely; it was very
> late and I was pretty groggy and hey, any network gear has to be
> telnet'table this day and age. Of course I was mostly wrong.
>
> The switch expects some signed payload before allowing a telnet
through. I
> found this: https://code.google.com/p/netgear-telnetenable/...but I'm
> having a hell of a time getting anything to respond.
>
> The most confounding part is the switch doesn't respond to a single SYN
> packet on low ports. I'm scanning all the ports now, but if nothing
shows
> up, I'm not sure what a payload is good for if the switch doesn't ACK a
> single SYN.
>
> I'm curious if anybody's got any tips besides not using Netgear in the
> datacenter.
>
> I have the MAC, I've IP'd it via DHCP, and the model number: JGS524E
and I
> can power cycle the switch as much as needed.
>
>
> P.S. long time listener, first time caller. i'm more of a sysadmin
> dangerously standing in for a proper network person.
> ------------------------------
>
> Seems to me that you need to use their "Switch Configuration Utility" to
> manage the switch. I didn't read all the documentation, but that is
what
> jumps out at me after a brief look. Maybe it will allow you to enable
> telnet or ssh from there. See the following link:
>

No windows box handy, nor the desire for that hoop.

...but what magic is a windows app going to perform to wake up an
unresponsive TCP stack?

In view that the application needs to be run directly on the LAN, I'm not
sure why you'd expect any TCP/IP like protocol - I asked a friend for a
packet capture and it seems that the configuration utility is using RRCP (
http://en.wikipedia.org/wiki/Realtek_Remote_Control_Protocol).

t'was finding this that made reassured me towards TCP/IP:
https://code.google.com/p/netgear-telnetenable/

but yes, i'd completely forgotten about other protocols.

HTH