[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [FW-1] MTU
The "ifconfig <interface> mtu <value>" command does work on IPSO, but the information gets re-written by the Voyager configuration at startup. Nokia says to put it into the rc.local file to be persistent across reboots, but I personally wouldn't do this. However temporarily changing it may help you troubleshoot. "ifconfig" displays the mtu size as 1500, but Voyager displays it as 1514. Both are right, it just depends upon what headers they count in the frames. If you are comparing the MTU size with what you are seeing in sniff traces use what "ifconfig" tells you. As for IPSO... It does not support Path MTU (PMTU) However this doesn't sound like your problem. Why is the router MTU lowered from the default? if you are messing with this then you have to make sure you are letting ICMP type 3 code 4 packets from one end of the connection to the other. Also make sure the router interface isn't configured to not send these packets (you should NOT have "no icmp unreachable" configured on the router interface. If you are still having more problems with this then provide more information, is this bi-directional problem? Is it just one router with the lowered MTU? etc.. Mitchell ____________________________________________________ http://www.attackprevention.com Information Security documents, articles, and policy > # ifconfig <interface> mtu <value> > > Are these Ethernet interfaces? The MTU is gonna be 1500. > > > -----Original Message----- > > From: [email protected] [mailto:[email protected]] > > Sent: Thursday, August 21, 2003 2:59 AM > > To: [email protected] > > Subject: Re: [FW-1] MTU > > > > Are you recieving ICMP messages as drop for this traffic at Checkpoint ? > > NG ? Which FP ? > > > > []'S > > > > ------------------------------------ > > Antonio Costa > > Odebrecht Engenharia e Construcao > > Infra-Estrutura de Rede e Seguranca > > [email protected] > > Tel.: +55-11-3443-9813 > > Fax.: +55-11-3443-9618 > > > > ----- Original Message ----- > > From: "v.r" <[email protected]> > > Date: Thursday, August 21, 2003 6:17 am > > Subject: [FW-1] MTU > > > > > Hello, > > > > > > We have a site to Site VPN between our sites built > > > bweteen CISCO VPN concentrators. Checkpoint firewall > > > is transparently sitting between them. > > > > > > The users on one side are able to ping the server on > > > the other end. And also able to open conncetions on > > > the other end. But they are not able to get the > > > webpages from the server. > > > > > > when we enquired, it has been found out that the mtu > > > settings on the router is 1440. > > > > > > will there be any settings of MTU in checkpoint on > > > NOKIA IPSO? > > > > > > and also is there any conflict of HTTP exists with MTU > > > change? ================================================= To set vacation, Out-Of-Office, or away messages, send an email to [email protected] in the BODY of the email add: set fw-1-mailinglist nomail ================================================= To unsubscribe from this mailing list, please see the instructions at http://www.checkpoint.com/services/mailing.html ================================================= If you have any questions on how to change your subscription options, email [email protected] =================================================
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