Bonding Capacity Calculator
Calculate aggregate bandwidth capacity of a bonded network interface across multiple NICs.
About Bonding Capacity Calculator
Not all Linux bonding modes deliver the same throughput characteristics despite combining the same physical links: mode 0 (balance-rr) round-robins packets across all links achieving full N× aggregate capacity even for a single flow but risks packet reordering; mode 1 (active-backup) uses exactly one link at a time purely for redundancy, so aggregate throughput is capped at a single link's speed regardless of link count; and mode 4 (802.3ad/LACP) creates a standards-based aggregate that switches also understand, delivering N× capacity in aggregate but typically hashing any individual flow to a single link, so a lone flow still can't exceed one link's speed.
Formula
Aggregate capacity by mode
mode0/mode4: aggregate = N × per_link_speed; mode1: aggregate = per_link_speed
- N
- number of bonded links
- S
- per-link speed
Worked example
With the default values below, Bonding Capacity Calculator returns Aggregate Bond Capacity (Mbps) of 4,000.0. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Per-Link Speed (Mbps)minimum 1
- 1,000
- Number of Bonded Links (N)minimum 1
- 4
- Bonding Modeone of Mode 0 — balance-rr (round-robin), Mode 1 — active-backup, Mode 4 — 802.3ad (LACP)
- Mode 4 — 802.3ad (LACP)
Results
- Aggregate Bond Capacity (Mbps)
- 4,000.0
- Max Throughput for a Single Flow (Mbps)
- 1,000.0
- Mode Behavior
- LACP (802.3ad) aggregates links into a true bundle, but any single flow is typically hashed to one link — aggregate N× bandwidth is only realized across many concurrent flows.
Step by step
- 1Values used
- 2Aggregate capacity by mode
- 3Aggregate Bond Capacity (Mbps)= 4,000.0
- 4Max Throughput for a Single Flow (Mbps)= 1,000.0
- 5Mode Behavior= LACP (802.3ad) aggregates links into a true bundle, but any single flow is typically hashed to one link — aggregate N× bandwidth is only realized across many concurrent flows.
Assumptions and limits
- The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 1 decimal place, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
Which bonding mode should I use for maximum single-flow throughput?
Mode 0 (balance-rr) is the only standard mode that can spread a single flow's packets across multiple links for combined throughput, but it requires a switch/network path tolerant of out-of-order delivery — most production LACP (mode 4) deployments instead rely on many concurrent flows to fill the aggregate, since any one flow is hashed to a single link.
Does LACP (mode 4) require switch-side configuration?
Yes — 802.3ad requires the connected switch ports to be configured as a matching LACP port channel/link aggregation group; without switch-side cooperation, LACP negotiation fails and the bond won't form (unlike active-backup or balance-rr, which work with unconfigured switch ports).
How do I check the current bonding mode and link status on Linux?
`cat /proc/net/bonding/<bond_name>` shows the active mode, all slave interfaces, and their individual link states (including which slave is currently active for active-backup mode).