Some travelers in Germany found their travel plans ruined on Sunday, a day ahead of planned 24-hour strikes called by two major unions, EVG and Verdi.

There was early disruption at Munich Airport because of the impending industrial action, while technical problems affecting German airline Lufthansa led to delays and cancellations at the country's largest air hub Frankfurt.

Transit troubles emerge in advance

Officials at Munich Airport, Germany's second-busiest airport, said that the Verdi union was hitting it with two consecutive days of strikes, rather than just one. The airport said there would be no passenger or cargo flights on either Sunday or Monday.

Some 1,500 connections were believed to be affected, with takeoffs and landings only possible for emergency humanitarian flights.

Separately to the strike, IT problems that slowed Lufthansa's operations at Frankfurt Airport — forcing cancellations — were resolved by early afternoon, the airline said.

However, problems continued to hamper passengers' ability to check in for Lufthansa flights, either online or at the machines at the airport. The technical disruptions had dogged external IT service providers, the airline said.

Last month, Lufthansa also struggled with IT issues because of damage during construction work, causing worldwide flight cancellations and delays.

There was extra traffic on the roads ahead of the strike as 10 of Germany's 16 states eased a Sunday ban on heavy goods vehicles carrying freight that might otherwise move by rail or ship.

However, Marcus Hover, vice general manager of North Rhine-Westphalia Association of Transport Economics and Logistics on Saturday said it was not expected to lead to the disruption of highway traffic.

What's happening on Monday?

Both the EVG railway union and the huge Verdi services union are combining forces to push for increased pay for their memberships amid persistent inflation.

Verdi last week said the union was calling for 120,000 workers — including security and ground workers at all German airports except in Berlin — to walk out.

Almost all major airports are on strike, including Frankfurt, Hamburg, Munich, and Stuttgart.

The German airport association ADV warned that as many as 380,000 airline travelers would not be able to take their flights because of the planned strikes.

The EVG union is calling for 230,000 workers at Germany's main railway operator Deutsche Bahn to walk out.

Deutsche Bahn has warned that it may not even be able to run an emergency timetable for long-distance trains on the strike day.

The state-owned rail service said regional trains would also be drastically scaled back.

Meanwhile, a strike of local transit employees in seven of Germany's 16 states will hit commuters taking shorter journeys.

Local buses and rail systems, including trams, are largely not expected to function because of the action in the states of Baden-Württemberg, Bavaria, Hesse, Lower Saxony, North Rhine-Westphalia, Rhineland-Palatinate, and Saxony.

Harbor employees and highway workers are also downing tools.

Staff at numerous locks on important waterways plan to strike as well as workers at Germany's largest port, Hamburg. Some highway tunnels could also be closed.

What are the issues?

Verdi wants a 10.5-percent salary rise, or at least 500 euros ($530) a month more, for public sector workers and higher bonus payments for airport staff who work on evenings and public holidays.

"The strike is necessary to make clear to employees that we will vehemently stand up for our demands," Verdi chair Frank Werneke was quoted as saying.

"It is a matter of survival for many thousands of employees to get a considerable pay rise," he said.

EVG is seeking a raise of 12% for its employees. Deutsche Bahn has offered a two-stage raise totaling 5%, as well as one-off payments.

Deutsche Bahn on Sunday said the strike was "completely excessive, groundless and unnecessary."

"Our employees and passengers now need a quick solution, not a big strike," Deutsche Bahn Human Resources director Martin Seiler said.

German rail union boss Martin Burkert on Friday admitted that strike action was a "sharp sword" but insisted that the unions were using it responsibly.

Berkert said the unions were expecting an offer suitable for negotiation ahead of talks with employers on April 24 and 25.

While German government spokesman Steffen Hebestreit noted on Friday that the right to strike is a fundamental one, he urged unions and transport employers to "find a viable solution that the effects of this strike are not too bad for the citizens of this country."

In a survey by the pollsters YouGov, there was overall support for the industrial action. Some 55% of respondents agreed it was justified for two major trade unions to jointly call for a day-long strike.