Solving IP ROUTE TABLE Overflow issue on Linksys Cisco SMB SG series switches

Home > Switch configuration notes > Solving IP ROUTE TABLE Overflow issue on Linksys Cisco SMB SG series switches

On old Linksys SMB switches which are rebranded as Cisco SG switches (eg SG300, SG450) while connected through command line (Console or SSH or Telnet) and adding route we may see following error:

%IPROUTETABLE-A-ROUTETABLEOVERFLOW: IP routing table overflow: failed to add route address

appearing repeatedly on the console.

To solve this we can use following steps:

1. Login into switch using Web browser
2. Go to "Routing Resources" sub-option under one of the top level menu options
3. You can validate here that no. of used (in use) routes and no. of maximum routes values match (Typically 128)
4. Change the default value of maximum entries from default of 128 to 400+ (Max acceptable value is displayed on the screen)

   Note that changing this value, requires / causes switch to reboot. Hence this should be done during downtime only.

5. After updating the value to sufficiently large no. the error should disappear. You can also see that "In use" value is now smaller than maximum value on the "Routing Resources" page

Refer:

• https://community.cisco.com/t5/small-business-switches/arp-e-arptbl-arp-table-overflow-aggregated-constantly-appearing/td-p/2508175

Home > Switch configuration notes > Solving IP ROUTE TABLE Overflow issue on Linksys Cisco SMB SG series switches