This is a correct explanation of the issue. Name resolution could have been ruled out by the info originally provided.
Jpc- I've seen this often. don't know about alcatel, but some vpn clients allow a mtu config option in the client software which is helpful to limit tcp payload per packet. Play around with it and you'll be rockin soon. good luck.byron -----Original Message----- From: Roger Seielstad [mailto:roger.seielstad@;inovis.com] Sent: Tuesday, October 29, 2002 9:01 AM To: Exchange Discussions Subject: RE: VPN breaks Outlook Neither - its not a name resolution issue, since you can connect to other host on your internal network. So, you'd be best off if you ignore Mr. Tener. Many of us have for months. See my previous post about MTU size. Outlook sets[1] the Do Not Fragment bit on much of its traffic with the server. So, it takes the 1516 or so bits, throws it into a packet, and sends it on its merry way. At which point the VPN client intercepts it[2], and encapsulates it into an IPSec packet. Which means an additional padding of about 56 bits for the IPSec header info. That makes the packet somewhere in the order of 1570 bits, and it gets slapped on the wire. Now, your friendly neighborhood[3] router sees that the packet is larger than it can handle (larger than its MTU size) and responds with an ICMP Packet must be fragmented but Don't Fragment bit set. The problem is that your client machine never sees that ICMP message, and so it doesn't automatically adjust its own MTU size down, and so Outlook chokes on sync. Roger ------------------------------------------------------ Roger D. Seielstad - MCSE Sr. Systems Administrator Inovis - Formerly Harbinger and Extricity Atlanta, GA [1] Stupidly - very very stupidly [2] Probably just like the Cisco clients - it shims the IP stack right around the MPR level [3] Actually, I believe it's the other end of the connection, not the local end, but that's really irrelevant. > -----Original Message----- > From: RBHATIA [mailto:RBHATIA@;AIIM.ORG] > Sent: Tuesday, October 29, 2002 9:18 AM > To: Exchange Discussions > Subject: RE: VPN breaks Outlook > > > Is it the LMHOSTS file or the HOSTS file ? > > -----Original Message----- > From: Tener, Richard [mailto:RTener@;midship.com] > Sent: Tuesday, October 29, 2002 9:24 AM > To: Exchange Discussions > Subject: RE: VPN breaks Outlook > > > yes you should use the lmhost file on the client pc to map to > your exchange > server thats what we use here at my office and it works good. > If you need > more help dont hesitate to email me. > > rich > > -----Original Message----- > From: JPC [mailto:jpciocon@;hotmail.com] > Sent: Monday, October 28, 2002 8:10 PM > To: Exchange Discussions > Subject: VPN breaks Outlook > > > Hi, folks: > > Mixed mode, currently migrating users from 5.5 to E2k. > Remote users have > Outlook 2002 on W2k Professional laptops and Alcatel PERMIT/Client. > > These users connect via dial-up, they can access their mailboxes and > send/receive no problem. When they use LinkSys router and DSL, they > can access our network, the internet and other network resources > EXCEPT for > their mailboxes on the E2k server. Synchronization failure > messages are > related to "network problems preventing access to the > Exchange server" or > the RPC message box "retrieving data from Exchange server". These > eventually fail and nothing is exchanged between the client and their > server mailbox. > > Has anyone seen this? If so, what tips would you suggest? > > Thanks very much. > -Juancho > > _________________________________________________________________ > List posting FAQ: http://www.swinc.com/resource/exch_faq.htm > Archives: http://www.swynk.com/sitesearch/search.asp > To unsubscribe: mailto:leave-exchange@;ls.swynk.com > Exchange List admin: [EMAIL PROTECTED] > > _________________________________________________________________ > List posting FAQ: http://www.swinc.com/resource/exch_faq.htm > Archives: http://www.swynk.com/sitesearch/search.asp > To unsubscribe: mailto:leave-exchange@;ls.swynk.com > Exchange List admin: [EMAIL PROTECTED] > > _________________________________________________________________ > List posting FAQ: http://www.swinc.com/resource/exch_faq.htm > Archives: http://www.swynk.com/sitesearch/search.asp > To unsubscribe: mailto:leave-exchange@;ls.swynk.com > Exchange List admin: [EMAIL PROTECTED] > _________________________________________________________________ List posting FAQ: http://www.swinc.com/resource/exch_faq.htm Archives: http://www.swynk.com/sitesearch/search.asp To unsubscribe: mailto:leave-exchange@;ls.swynk.com Exchange List admin: [EMAIL PROTECTED] _________________________________________________________________ List posting FAQ: http://www.swinc.com/resource/exch_faq.htm Archives: http://www.swynk.com/sitesearch/search.asp To unsubscribe: mailto:leave-exchange@;ls.swynk.com Exchange List admin: [EMAIL PROTECTED]
