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New Member

MTU size.......!

Hi all,

what kind of problems one may face if there is an MTU size mismatch problem in the LAN? How to tackle the problem if it persists?

The back-up for one of the servers is not taking place, while the other server of same subnet is getting back-up daily without fail. Do we have some recommendations on what should be the switchport mtu settings and all, if this port is connected to a ASA-5550 firewall.


New Member

Re: MTU size.......!

you must be sure that the MTU is the same on all the equipments including servers, the default is 1500. On switches for example it is not shown with the show running command by default unless someone have changed it

I got some issues with MTU, I have to be sure of the MTU configured on all switches , routers and firewalls (I left the default MTU parameters) were the same and I configured the ip virtual-reassembly interface command on my router, it works to me

See this link, it is about ip virtual reassambly concepts and how to configure it

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