Very Computer

A week ago I posted a question on getting SLIP working. I got an answer. I
also got a lot of questions like 'Yeah, I've got the same problem. Can you
send me any answers you get...'. This and the fact that my rmailfile got
completely screwed up this morning (and I lost the adresses of the people
requesting an answer) is the reason I post here. (I hope c.o.l.admin is the
best group to post to. Where is c.o.l.networking? :-))

Original question (abreviated):

Quote:>I recently installed LINUX on my 486 machine. Last weekend I tried to get SLIP
>working. It works only half: I can get UDP connections but I cannot get TCP
>connections!

>So 'ping' and some tools using UDP that I wrote myself work great, but the
>more usefull tools like telnet, ftp, and remote X-connections block after
>connecting.  For example, FTP gets to the point where it tells me 'connected
>to bla.foo.bar.timbuktu' and then is as responsive as a dodo.

 <stuff deleted about kernel pl11 and SLS 1.0.3-out-of-the-box>

Quote:> I'll lay you any odds that it's SLIP header compression. 99pl11 added
> header compression (CSLIP). So yourassociates are not using CSLIP and
> you are. If you are talking to a SLIP server which doesn't do CSLIP,
> only UDP datagrams will get through (they never get their headers
> compressed). The fix is to go to linux/net/inet/slip.c

> In sl_encaps, there is a line beginning

>   len = slhc_compress(...
> Comment out this line and you will stop sending CSLIP packets. You don't
> need to alter the code for receiving CSLIP, though you can if you want.
> To do this, go to the routine sl_bump. There's an if(1) around a big
> block of code for receiving CSLIP. Change it to if(0).

It works for me!

Notice also that you should set your 'mtu' not too high. I use 256. Otherwise
you may get effects like: 'I can get the first few Kbytes and then the link
blocks'.

--

 - DARK IN HERE, ISN'T IT?
(Signature still under construction... -For over four years- Be very patient.)

question:

Quote:>>I recently installed LINUX on my 486 machine. Last weekend I tried to get SLIP
>>working. It works only half: I can get UDP connections but I cannot get TCP
>>connections!
answer:
>> I'll lay you any odds that it's SLIP header compression. 99pl11 added
>> header compression (CSLIP). So yourassociates are not using CSLIP and
>> you are. If you are talking to a SLIP server which doesn't do CSLIP,
>> only UDP datagrams will get through (they never get their headers
>> compressed). The fix is to go to linux/net/inet/slip.c

Anyway,
        I have had 'similar' problems recently. Using pl11 with CSLIP configed,
I can use telnet, ftp, and other tcp functions. But, I could not use NFS. This
was a big problem for me. Experimentation and recompilation showed me that with
CSLIP off ( just using SLIP ) the amount of error in each packet decreased
significantly, yet, there was still some error. I believe this error is
associated with the calculation of packet lenghts.
        But, using pl10 kernels, or, using a pl10 client and pl11 server, I can
use NFS. But, without CSLIP on both ends, I can't use tcp, only udp.

Has anyone else noticed this problem? As soon as I find a fix, I'll post.

regards,

Joe Battle