CAI, 2nd installation

[mdulcey at pryder.pn.com (Mark J. Dulcey)]

On Mon, 27 Oct 1997, Rich Braun wrote:

> * You get a static IP address in one of their class-C blocks.  Inverse
>   DNS isn't configured at this point, which is inconvenient when trying to
>   connect to certain servers out there (e.g. ftp.uu.net rejects my attempts).
>   I'll see if they'll point it to one of my domains.

I discovered the lack of inverse DNS, too -- oddly enough, on an attempt
at the same site, ftp.uu.net.  Most other FTP servers out there aren't
configured to insist on working reverse DNS.

> * Performance is over 10x my old 128K ISDN connection.  I get a consistent
>   160K bytes/second (about 83% of a T1, better than I usually get on a
>   T1) when doing an ftp from my old standby wizard.pn.com; I also
>   tried a few other hosts at this busy Monday afternoon hour:  tsx-11.mit.edu,
>   115K; www.caiwireless.net, 47K; ftp.zdnet.com, 68K.  The 128K ISDN
>   connection tops out at 15K.  These speeds are observed using QVT/Net's
>   ftp client on a Win95 box using either the PPP server supplied by CAI or
>   the ISDN server at my old ISP; I didn't see much difference.  The
>   benchmarks were done using gzipped files; compression isn't a factor.

I couldn't quite duplicate Rich's results on my Linux box, but I did get
116K/second on an FTP from wizard.pn.com.  I also got close to 100K on an
HTTP download from www.microsoft.com.

> * CAI's DNS server configured by the tech on my box was down at the time.
>   Not impressive from a technical standpoint.  This was causing long
>   timeouts doing lookups on web pages, until I switched DNS servers.  (The
>   secondaries they supply are cache servers at UUNET.)  After fixing this,
>   I was able to zip through the boston.com web pages detailing the latest
>   stock-market meltdown...

Yup, I've seen this one the last couple of days.  CAI's local DNS was
working when I first set things up, but isn't working now.

> * The tech also had to apologize for the fact that my PPP and POP3 logins
>   weren't yet configured; he explained that the back-office folks weren't
>   aware he was able to dispatch this installation today, after noting that
>   he "wasn't surprised" that the logins were yet to be configured.

They STILL don't have my POP3 or shell logins working (meaning no access
to web space). I'm still using my POP3 box at my old ISP, using the
wireless connection to download the mail (very quickly, I might add).

> I'll find time the next few days to get the Linux box configured as a
> masquerade gateway.  Looks to me like inbound packets will go to the
> Linux box in the 208.221.212.xx network and get routed to a
> 192.168.x.x net I assign for the PC's, and outbound packets will go
> through the 192.168.100.1 address they assigned to the Ethernet port
> on the General Instruments box.  I can set up the Linux box as a
> caching DNS server and ignore the DNS server problems at the ISP.

I've got masquerading set up here, and it's working nicely.  I built a
brand new 2.0.31 kernel (it came out recently) with the proper options (my
previous 2.0.30 didn't have masquerading enabled), and experimented a bit.
It didn't work until I changed the primary IP address of my Ethernet
interface to the one assigned by CAI.  I now use an IP alias to add the
address used on my LAN.  (Yes, it's all happening with the one card.)  I
also had to set up a route to the Surfboard, and a default route to the
Internet using it.  My local LAN is 192.168.2.x, so these are the commands
I had to add:

ifconfig eth0:0 192.168.2.1
route add -net 192.168.2.0 eth0:0
route add -host 192.168.100.1 eth0
route add default gw 192.168.100.1

By the way, the same FTP transfer from wizard.pn.com, done from Windows 95
and masqueraded through Linux, could only manage 26K.  There may be some
tuning to do on the masquerade setup to get full speed.  It's also
possible that using separate Ethernets would help; I may try adding a
second card to the Linux box to see what happens.