Networking – what happens when router memory filled?


what happens when router memory filling ?
i know that router when memory filled after isn't net available and internet is turn off before router do not make router restart .
and else interested me. what moment fill memory ?

asus memory .

Best Answer

There's quite a few things that can go wrong if your router runs out of memory. This is assuming a SOHO router running Linux or other embedded operating system. Business/carrier grade routers may act differently.

  • Tracking TCP connections requires a bit of memory from the system doing so. If a router's memory is completely full, it may not respond to incoming TCP connections, making them drop. Existing ones should continue to work.

  • Tracking NAT sessions also requires a bit of memory per incoming request. If memory is completely full, your system may fail to forward new connections to the Internet or be unable to forward incoming connections. This would affect any incoming IP protocol, not just TCP.

  • The embedded web server on your router providing the web interface will either create a new process to satifsy attempts to access it, or allocate more memory to handle the request. If RAM is full, this can't happen, and the router's web interface may not work at all, or certain assets won't load, or may have trouble loading.

  • A similar situation exists for any telnet or SSH server running on the router. Your router may be unable to spawn a login process or shell if there is not enough RAM.

  • A similar situation exists for any service running on your router, such as dnsmasq or any DHCP server. It may be unable to allocate memory or spawn processes to handle new requests and may stop responding. Some services may terminate abnormally if that happens, some may just stop responding.

256MB is a lot of memory for a router so you should not run into any issues unless you are doing something really weird.