Mohan
Information on any COMMAND will be returned by one/all of:$ COMMAND --help$ man COMMAND$ info COMMAND
$ man pppdexplains all pppd related issues, from which I have copied out the below.Also there are often explanations within cogent options files like/etc/ppp/options,as you noted.
If both sides are competent, MRU and MNU will be auto chosen duringthe negotiation between modem and the IP hot
MarvS======== mru nSet the MRU [Maximum Receive Unit] value to n. Pppd will ask the peerto send packets of no more than n bytes. The value of n mustbe between 128 and 16384; the default is 1500. A value of 296 workswell on very slow links (40 bytes for TCP/IP header + 256 bytes ofdata). Note that for the IPv6 protocol, the MRU must be at least1280.
mtu nSet the MTU [Maximum Transmit Unit] value to n. Unless the peerrequests a smaller value via MRU negotiation, pppd will request thatthe kernel networking code send data packets of no more than n bytesthrough the PPP network interface. Note that for the IPv6 protocol,the MTU must be at least 1280.
On 6/12/07, Mohan Sai <k_mohansai@xxxxxxx> wrote:> Marvs>> I have already tried with "Init2 = ATQ0 V1 E1 S0=0 &C1 &D2 +MS=34" .> It seemed stable than +MS=90 but the network throughput (data download)> came down.>> There doesn't seem to be any figure mentioned for mtu in the> etc/ppp/options file it has been commented. What figure was it using> earlier and is acceptable (I mean the range) for mtu. Also throw some> light on mru and -mru and how any alteration of them could help me. An> answer to this I think would also serve as future reference to other> linmodem group members as well, as and when they need it.>> thanks,> mohan sai>> On Sun, 2007-06-10 at 20:05 -0400, Marvin Stodolsky wrote:> > Mohan,> >> > Seems like a poor line quality problem.> > Not a driver problem per se.> > Go through the points of the PostInstall Howto at> > http://132.68.73.235/linmodems/index.html> > Within /etc/ppp/options decreasing the MTU size may help> > Also try dropping from MS=90 to MS=34 with> > Init2 = ATQ0 V1 E1 S0=0 &C1 &D2 +MS=34> >> > MarvS> >> > On 6/10/07, Mohan Sai <k_mohansai@xxxxxxx> wrote:> > > Hi Marvs:> > >> > > I had seen this suggestion of yours in response to someone's similar> > > problem earlier & already followed those instrutions. My username and> > > password were written nicely to /etc/ppp/pap-secrets & chap-secrets> > > files.The problem is recurring despite having a proper username and> > > passwrod in the above two files.> > >> > > I am sometimes able to connect but with an unstable connection. At few> > > other times, it doesn't even log me in quoting error 16 (a modem has> > > hung up). I would like to know how to prevent the modem from hanging by> > > itself thereby destabilizing the connection as it happened below.> > >> > > thanks,> > > Mohan Sai> > >> > >> > > On Sat, 2007-06-09 at 22:25 -0400, Marvin Stodolsky wrote:> > > > Mohan> > > >> > > > See> > > > In case of a message like:> > > > Warning: Could not modify /etc/ppp/pap-secrets: Permission denied> > > > see http://linmodems.technion.ac.il/bigarch/archive-sixth/msg04656.html> > > >> > > > MarvS> > > >> > > > On 6/9/07, Mohan Sai <k_mohansai@xxxxxxx> wrote:> > > > > Hello!!> > > > > Can somebody help me solve the below problem wherein I get disconnected> > > > > time and again while trying to connect. Any help will be appreciated.> > > > > regards,> > > > > Mohan Sai> > > > >> > > > >> > > > > mohansai@aumsairam:~$ wvdial --> WvDial: Internet dialer version 1.55> > > > > --> Cannot get information for serial port.> > > > > --> Initializing modem.> > > > > --> Sending: ATZ> > > > > ATZ> > > > > OK> > > > > --> Sending: ATQ0 V1 E1 S0=0 &C1 &D2 +MS=90> > > > > ATQ0 V1 E1 S0=0 &C1 &D2 +MS=90> > > > > OK> > > > > --> Sending: ATM1> > > > > ATM1> > > > > OK> > > > > --> Modem initialized.> > > > > --> Sending: ATDT172233> > > > > --> Waiting for carrier.> > > > > ATDT172233> > > > > CONNECT 50667> > > > > --> Carrier detected. Starting PPP immediately.> > > > > --> Starting pppd at Sun Jun 10 07:16:49 2007> > > > > --> Warning: Could not modify /etc/ppp/pap-secrets: Permission denied> > > > > --> --> PAP (Password Authentication Protocol) may be flaky.> > > > > --> Warning: Could not modify /etc/ppp/chap-secrets: Permission denied> > > > > --> --> CHAP (Challenge Handshake) may be flaky.> > > > > --> Pid of pppd: 6160> > > > > --> pppd: �[7f]��@�[05][08]��[05][08]> > > > > --> Using interface ppp0> > > > > --> pppd: �[7f]��@�[05][08]��[05][08]> > > > > --> pppd: �[7f]��@�[05][08]��[05][08]> > > > > --> pppd: �[7f]��@�[05][08]��[05][08]> > > > > --> pppd: �[7f]��@�[05][08]��[05][08]> > > > > --> pppd: �[7f]��@�[05][08]��[05][08]> > > > > --> pppd: �[7f]��@�[05][08]��[05][08]> > > > > --> pppd: �[7f]��@�[05][08]��[05][08]> > > > > --> pppd: �[7f]��@�[05][08]��[05][08]> > > > > --> pppd: �[7f]��@�[05][08]��[05][08]> > > > > --> pppd: �[7f]��@�[05][08]��[05][08]> > > > > --> pppd: �[7f]��@�[05][08]��[05][08]> > > > > --> pppd: �[7f]��@�[05][08]��[05][08]> > > > > --> pppd: �[7f]��@�[05][08]��[05][08]> > > > > --> pppd: �[7f]��@�[05][08]��[05][08]> > > > > --> pppd: �[7f]��@�[05][08]��[05][08]> > > > > --> pppd: �[7f]��@�[05][08]��[05][08]> > > > > --> pppd: �[7f]��@�[05][08]��[05][08]> > > > > --> pppd: �[7f]��@�[05][08]��[05][08]> > > > > --> pppd: �[7f]��@�[05][08]��[05][08]> > > > > --> Disconnecting at Sun Jun 10 07:17:20 2007> > > > > --> The PPP daemon has died: A modem hung up the phone (exit code = 16)> > > > > --> man pppd explains pppd error codes in more detail.> > > > > --> Try again and look into /var/log/messages and the wvdial and pppd> > > > > man pages for more information.> > > > >> > > > >> > > > >> > >> > >>>
